From ca39b260704b97abb1297633b6b36bdfca5b9a10 Mon Sep 17 00:00:00 2001
From: Zach Gollwitzer <zach@maybe.co>
Date: Wed, 19 Jun 2024 06:52:08 -0400
Subject: [PATCH] Transaction transfers, payments, and matching (#883)

* Add transfer model and clean up family snapshot fixtures

* Ignore transfers in income and expense snapshots

* Add transfer validations

* Implement basic transfer matching UI

* Fix merge conflicts

* Add missing translations

* Tweak selection states for transfer types

* Add missing i18n translation
---
 .../stylesheets/application.tailwind.css      |   4 +
 app/controllers/transactions_controller.rb    |  28 ++-
 app/controllers/transfers_controller.rb       |  41 ++++
 app/helpers/application_form_builder.rb       |   2 +-
 app/helpers/transactions_helper.rb            |  23 +++
 app/helpers/transfers_helper.rb               |   2 +
 .../controllers/bulk_select_controller.js     |   2 +-
 app/models/family.rb                          |  39 ++--
 app/models/transaction.rb                     |  25 ++-
 app/models/transfer.rb                        |  57 ++++++
 .../transactions/_transaction.html.erb        |   9 +-
 app/views/transactions/_date_group.html.erb   |  19 +-
 app/views/transactions/_form.html.erb         |  13 +-
 app/views/transactions/_name.html.erb         |   2 +-
 .../transactions/_selection_bar.html.erb      |  15 ++
 app/views/transactions/_transaction.html.erb  |  39 +++-
 app/views/transactions/index.html.erb         |   4 +-
 app/views/transactions/show.html.erb          |  64 +++----
 app/views/transfers/_form.html.erb            |  32 ++++
 app/views/transfers/_transfer.html.erb        |  37 ++++
 app/views/transfers/new.html.erb              |  17 ++
 config/locales/views/transactions/en.yml      |  14 +-
 config/locales/views/transfers/en.yml         |  27 +++
 config/routes.rb                              |   4 +
 db/migrate/20240614120946_create_transfers.rb |   7 +
 ...1110_add_transfer_fields_to_transaction.rb |   8 +
 db/schema.rb                                  |  13 +-
 .../transactions_controller_test.rb           |   6 +-
 test/controllers/transfers_controller_test.rb |  33 ++++
 test/fixtures/account/credits.yml             |   3 +-
 test/fixtures/account/cryptos.yml             |  12 +-
 test/fixtures/account/depositories.yml        |  12 +-
 test/fixtures/account/expected_balances.csv   |  32 ----
 test/fixtures/account/investments.yml         |   1 +
 test/fixtures/account/loans.yml               |   1 +
 test/fixtures/account/other_assets.yml        |   5 +-
 test/fixtures/account/other_liabilities.yml   |   1 +
 test/fixtures/account/properties.yml          |   1 +
 test/fixtures/account/vehicles.yml            |   1 +
 test/fixtures/account_balances.yml            |  13 --
 test/fixtures/accounts.yml                    |  61 ++++--
 test/fixtures/exchange_rates.yml              |  73 +++++++
 test/fixtures/family/expected_snapshots.csv   |  32 ----
 test/fixtures/files/.keep                     |   0
 .../files/expected_family_snapshots.csv       |  33 ++++
 test/fixtures/transactions.yml                |  65 ++++++-
 test/fixtures/transfers.yml                   |   2 +
 test/fixtures/valuations.yml                  |  44 ++++-
 .../models/account/balance/calculator_test.rb | 179 ++++++++----------
 test/models/account/syncable_test.rb          |  38 ++--
 test/models/account_test.rb                   |  31 +--
 test/models/family_test.rb                    | 107 ++++++-----
 test/models/transaction_test.rb               |  11 ++
 test/models/transfer_test.rb                  |  49 +++++
 test/models/value_group_test.rb               |   2 +-
 test/support/family_snapshot_test_helper.rb   |  21 ++
 test/system/transactions_test.rb              |   2 +-
 57 files changed, 991 insertions(+), 427 deletions(-)
 create mode 100644 app/controllers/transfers_controller.rb
 create mode 100644 app/helpers/transfers_helper.rb
 create mode 100644 app/models/transfer.rb
 create mode 100644 app/views/transfers/_form.html.erb
 create mode 100644 app/views/transfers/_transfer.html.erb
 create mode 100644 app/views/transfers/new.html.erb
 create mode 100644 config/locales/views/transfers/en.yml
 create mode 100644 db/migrate/20240614120946_create_transfers.rb
 create mode 100644 db/migrate/20240614121110_add_transfer_fields_to_transaction.rb
 create mode 100644 test/controllers/transfers_controller_test.rb
 delete mode 100644 test/fixtures/account/expected_balances.csv
 delete mode 100644 test/fixtures/account_balances.yml
 delete mode 100644 test/fixtures/family/expected_snapshots.csv
 delete mode 100644 test/fixtures/files/.keep
 create mode 100644 test/fixtures/files/expected_family_snapshots.csv
 create mode 100644 test/fixtures/transfers.yml
 create mode 100644 test/models/transfer_test.rb
 create mode 100644 test/support/family_snapshot_test_helper.rb

diff --git a/app/assets/stylesheets/application.tailwind.css b/app/assets/stylesheets/application.tailwind.css
index 2ffebf12..00fb5d95 100644
--- a/app/assets/stylesheets/application.tailwind.css
+++ b/app/assets/stylesheets/application.tailwind.css
@@ -7,6 +7,10 @@
   details > summary::-webkit-details-marker {
     @apply hidden;
   }
+
+  details > summary {
+    @apply list-none;
+  }
 }
 
 @layer components {
diff --git a/app/controllers/transactions_controller.rb b/app/controllers/transactions_controller.rb
index bc2a9592..0c569d96 100644
--- a/app/controllers/transactions_controller.rb
+++ b/app/controllers/transactions_controller.rb
@@ -9,9 +9,9 @@ class TransactionsController < ApplicationController
     @pagy, @transactions = pagy(result, items: 50)
 
     @totals = {
-      count: result.count,
-      income: result.inflows.sum(&:amount_money).abs,
-      expense: result.outflows.sum(&:amount_money).abs
+      count: result.select { |t| t.currency == Current.family.currency }.count,
+      income: result.income_total(Current.family.currency).abs,
+      expense: result.expense_total(Current.family.currency)
     }
   end
 
@@ -54,7 +54,7 @@ class TransactionsController < ApplicationController
 
   def bulk_delete
     destroyed = Current.family.transactions.destroy_by(id: bulk_delete_params[:transaction_ids])
-    redirect_to transactions_url, notice: t(".success", count: destroyed.count)
+    redirect_back_or_to transactions_url, notice: t(".success", count: destroyed.count)
   end
 
   def bulk_edit
@@ -63,13 +63,31 @@ class TransactionsController < ApplicationController
   def bulk_update
     transactions = Current.family.transactions.where(id: bulk_update_params[:transaction_ids])
     if transactions.update_all(bulk_update_params.except(:transaction_ids).to_h.compact_blank!)
-      redirect_to transactions_url, notice: t(".success", count: transactions.count)
+      redirect_back_or_to transactions_url, notice: t(".success", count: transactions.count)
     else
       flash.now[:error] = t(".failure")
       render :index, status: :unprocessable_entity
     end
   end
 
+  def mark_transfers
+    Current.family
+           .transactions
+           .where(id: bulk_update_params[:transaction_ids])
+           .mark_transfers!
+
+    redirect_back_or_to transactions_url, notice: t(".success")
+  end
+
+  def unmark_transfers
+    Current.family
+           .transactions
+           .where(id: bulk_update_params[:transaction_ids])
+           .update_all marked_as_transfer: false
+
+    redirect_back_or_to transactions_url, notice: t(".success")
+  end
+
   private
 
     def set_transaction
diff --git a/app/controllers/transfers_controller.rb b/app/controllers/transfers_controller.rb
new file mode 100644
index 00000000..6e231a88
--- /dev/null
+++ b/app/controllers/transfers_controller.rb
@@ -0,0 +1,41 @@
+class TransfersController < ApplicationController
+  layout "with_sidebar"
+
+  before_action :set_transfer, only: :destroy
+
+  def new
+    @transfer = Transfer.new
+  end
+
+  def create
+    from_account = Current.family.accounts.find(transfer_params[:from_account_id])
+    to_account = Current.family.accounts.find(transfer_params[:to_account_id])
+
+    @transfer = Transfer.build_from_accounts from_account, to_account, \
+                                             date: transfer_params[:date],
+                                             amount: transfer_params[:amount].to_d,
+                                             currency: transfer_params[:currency],
+                                             name: transfer_params[:name]
+
+    if @transfer.save
+      redirect_to transactions_path, notice: t(".success")
+    else
+      render :new, status: :unprocessable_entity
+    end
+  end
+
+  def destroy
+    @transfer.destroy_and_remove_marks!
+    redirect_back_or_to transactions_url, notice: t(".success")
+  end
+
+  private
+
+    def set_transfer
+      @transfer = Transfer.find(params[:id])
+    end
+
+    def transfer_params
+      params.require(:transfer).permit(:from_account_id, :to_account_id, :amount, :currency, :date, :name)
+    end
+end
diff --git a/app/helpers/application_form_builder.rb b/app/helpers/application_form_builder.rb
index dc3df84b..0e33c222 100644
--- a/app/helpers/application_form_builder.rb
+++ b/app/helpers/application_form_builder.rb
@@ -25,7 +25,7 @@ class ApplicationFormBuilder < ActionView::Helpers::FormBuilder
   # See `Monetizable` concern, which adds a _money suffix to the attribute name
   # For a monetized field, the setter will always be the attribute name without the _money suffix
   def money_field(method, options = {})
-    money = @object.send(method)
+    money = @object && @object.respond_to?(method) ? @object.send(method) : nil
     raise ArgumentError, "The value of #{method} is not a Money object" unless money.is_a?(Money) || money.nil?
 
     money_amount_method = method.to_s.chomp("_money").to_sym
diff --git a/app/helpers/transactions_helper.rb b/app/helpers/transactions_helper.rb
index f5f4e9c4..67758978 100644
--- a/app/helpers/transactions_helper.rb
+++ b/app/helpers/transactions_helper.rb
@@ -17,4 +17,27 @@ module TransactionsHelper
       content: content
     }
   end
+
+  def unconfirmed_transfer?(transaction)
+    transaction.marked_as_transfer && transaction.transfer.nil?
+  end
+
+  def group_transactions_by_date(transactions)
+    grouped_by_date = {}
+
+    transactions.each do |transaction|
+      if transaction.transfer
+        transfer_date = transaction.transfer.inflow_transaction.date
+        grouped_by_date[transfer_date] ||= { transactions: [], transfers: [] }
+        unless grouped_by_date[transfer_date][:transfers].include?(transaction.transfer)
+          grouped_by_date[transfer_date][:transfers] << transaction.transfer
+        end
+      else
+        grouped_by_date[transaction.date] ||= { transactions: [], transfers: [] }
+        grouped_by_date[transaction.date][:transactions] << transaction
+      end
+    end
+
+    grouped_by_date
+  end
 end
diff --git a/app/helpers/transfers_helper.rb b/app/helpers/transfers_helper.rb
new file mode 100644
index 00000000..98355baf
--- /dev/null
+++ b/app/helpers/transfers_helper.rb
@@ -0,0 +1,2 @@
+module TransfersHelper
+end
diff --git a/app/javascript/controllers/bulk_select_controller.js b/app/javascript/controllers/bulk_select_controller.js
index a1aff137..71a82149 100644
--- a/app/javascript/controllers/bulk_select_controller.js
+++ b/app/javascript/controllers/bulk_select_controller.js
@@ -113,7 +113,7 @@ export default class extends Controller {
   #updateGroups() {
     this.groupTargets.forEach(group => {
       const rows = this.rowTargets.filter(row => group.contains(row))
-      const groupSelected = rows.every(row => this.selectedIdsValue.includes(row.dataset.id))
+      const groupSelected = rows.length > 0 && rows.every(row => this.selectedIdsValue.includes(row.dataset.id))
       group.querySelector("input[type='checkbox']").checked = groupSelected
     })
   }
diff --git a/app/models/family.rb b/app/models/family.rb
index 3b644bac..d7ccafd9 100644
--- a/app/models/family.rb
+++ b/app/models/family.rb
@@ -10,16 +10,16 @@ class Family < ApplicationRecord
 
   def snapshot(period = Period.all)
     query = accounts.active.joins(:balances)
-      .where("account_balances.currency = ?", self.currency)
-      .select(
-        "account_balances.currency",
-        "account_balances.date",
-        "SUM(CASE WHEN accounts.classification = 'liability' THEN account_balances.balance ELSE 0 END) AS liabilities",
-        "SUM(CASE WHEN accounts.classification = 'asset' THEN account_balances.balance ELSE 0 END) AS assets",
-        "SUM(CASE WHEN accounts.classification = 'asset' THEN account_balances.balance WHEN accounts.classification = 'liability' THEN -account_balances.balance ELSE 0 END) AS net_worth",
-      )
-      .group("account_balances.date, account_balances.currency")
-      .order("account_balances.date")
+              .where("account_balances.currency = ?", self.currency)
+              .select(
+                "account_balances.currency",
+                "account_balances.date",
+                "SUM(CASE WHEN accounts.classification = 'liability' THEN account_balances.balance ELSE 0 END) AS liabilities",
+                "SUM(CASE WHEN accounts.classification = 'asset' THEN account_balances.balance ELSE 0 END) AS assets",
+                "SUM(CASE WHEN accounts.classification = 'asset' THEN account_balances.balance WHEN accounts.classification = 'liability' THEN -account_balances.balance ELSE 0 END) AS net_worth",
+              )
+              .group("account_balances.date, account_balances.currency")
+              .order("account_balances.date")
 
     query = query.where("account_balances.date >= ?", period.date_range.begin) if period.date_range.begin
     query = query.where("account_balances.date <= ?", period.date_range.end) if period.date_range.end
@@ -35,15 +35,16 @@ class Family < ApplicationRecord
   def snapshot_account_transactions
     period = Period.last_30_days
     results = accounts.active.joins(:transactions)
-      .select(
-        "accounts.*",
-        "COALESCE(SUM(amount) FILTER (WHERE amount > 0), 0) AS spending",
-        "COALESCE(SUM(-amount) FILTER (WHERE amount < 0), 0) AS income"
-      )
-      .where("transactions.date >= ?", period.date_range.begin)
-      .where("transactions.date <= ?", period.date_range.end)
-      .group("id")
-      .to_a
+                .select(
+                  "accounts.*",
+                  "COALESCE(SUM(amount) FILTER (WHERE amount > 0), 0) AS spending",
+                  "COALESCE(SUM(-amount) FILTER (WHERE amount < 0), 0) AS income"
+                )
+                .where("transactions.date >= ?", period.date_range.begin)
+                .where("transactions.date <= ?", period.date_range.end)
+                .where("transactions.marked_as_transfer = ?", false)
+                .group("id")
+                .to_a
 
     results.each do |r|
       r.define_singleton_method(:savings_rate) do
diff --git a/app/models/transaction.rb b/app/models/transaction.rb
index 4ffdc137..1d6b304e 100644
--- a/app/models/transaction.rb
+++ b/app/models/transaction.rb
@@ -4,6 +4,7 @@ class Transaction < ApplicationRecord
   monetize :amount
 
   belongs_to :account
+  belongs_to :transfer, optional: true
   belongs_to :category, optional: true
   belongs_to :merchant, optional: true
   has_many :taggings, as: :taggable, dependent: :destroy
@@ -42,6 +43,10 @@ class Transaction < ApplicationRecord
     amount > 0
   end
 
+  def transfer?
+    marked_as_transfer
+  end
+
   def sync_account_later
     if destroyed?
       sync_start_date = previous_transaction_date
@@ -53,6 +58,21 @@ class Transaction < ApplicationRecord
   end
 
   class << self
+    def income_total(currency = "USD")
+      inflows.reject(&:transfer?).select { |t| t.currency == currency }.sum(&:amount_money)
+    end
+
+    def expense_total(currency = "USD")
+      outflows.reject(&:transfer?).select { |t| t.currency == currency }.sum(&:amount_money)
+    end
+
+    def mark_transfers!
+      update_all marked_as_transfer: true
+
+      # Attempt to "auto match" and save a transfer if 2 transactions selected
+      Transfer.new(transactions: all).save if all.count == 2
+    end
+
     def daily_totals(transactions, period: Period.last_30_days, currency: Current.family.currency)
       # Sum spending and income for each day in the period with the given currency
       select(
@@ -60,7 +80,7 @@ class Transaction < ApplicationRecord
         "COALESCE(SUM(converted_amount) FILTER (WHERE converted_amount > 0), 0) AS spending",
         "COALESCE(SUM(-converted_amount) FILTER (WHERE converted_amount < 0), 0) AS income"
       )
-        .from(transactions.with_converted_amount(currency), :t)
+        .from(transactions.with_converted_amount(currency).where(marked_as_transfer: false), :t)
         .joins(sanitize_sql([ "RIGHT JOIN generate_series(?, ?, interval '1 day') AS gs(date) ON t.date = gs.date", period.date_range.first, period.date_range.last ]))
         .group("gs.date")
     end
@@ -83,7 +103,7 @@ class Transaction < ApplicationRecord
     end
 
     def search(params)
-      query = all
+      query = all.includes(:transfer)
       query = query.by_name(params[:search]) if params[:search].present?
       query = query.with_categories(params[:categories]) if params[:categories].present?
       query = query.with_accounts(params[:accounts]) if params[:accounts].present?
@@ -96,7 +116,6 @@ class Transaction < ApplicationRecord
   end
 
   private
-
     def previous_transaction_date
       self.account
           .transactions
diff --git a/app/models/transfer.rb b/app/models/transfer.rb
new file mode 100644
index 00000000..bb3778fb
--- /dev/null
+++ b/app/models/transfer.rb
@@ -0,0 +1,57 @@
+class Transfer < ApplicationRecord
+  has_many :transactions, dependent: :nullify
+
+  validate :transaction_count, :from_different_accounts, :net_zero_flows, :all_transactions_marked
+
+  def inflow_transaction
+    transactions.find { |t| t.inflow? }
+  end
+
+  def outflow_transaction
+    transactions.find { |t| t.outflow? }
+  end
+
+  def destroy_and_remove_marks!
+    transaction do
+      transactions.each do |t|
+        t.update! marked_as_transfer: false
+      end
+
+      destroy!
+    end
+  end
+
+  class << self
+    def build_from_accounts(from_account, to_account, date:, amount:, currency:, name:)
+      outflow = from_account.transactions.build(amount: amount.abs, currency: currency, date: date, name: name, marked_as_transfer: true)
+      inflow = to_account.transactions.build(amount: -amount.abs, currency: currency, date: date, name: name, marked_as_transfer: true)
+
+      new transactions: [ outflow, inflow ]
+    end
+  end
+
+  private
+
+    def transaction_count
+      unless transactions.size == 2
+        errors.add :transactions, "must have exactly 2 transactions"
+      end
+    end
+
+    def from_different_accounts
+      accounts = transactions.map(&:account_id).uniq
+      errors.add :transactions, "must be from different accounts" if accounts.size < transactions.size
+    end
+
+    def net_zero_flows
+      unless transactions.sum(&:amount).zero?
+        errors.add :transactions, "must have an inflow and outflow that net to zero"
+      end
+    end
+
+    def all_transactions_marked
+      unless transactions.all?(&:marked_as_transfer)
+        errors.add :transactions, "must be marked as transfer"
+      end
+    end
+end
diff --git a/app/views/accounts/transactions/_transaction.html.erb b/app/views/accounts/transactions/_transaction.html.erb
index c117eb3b..5adc5817 100644
--- a/app/views/accounts/transactions/_transaction.html.erb
+++ b/app/views/accounts/transactions/_transaction.html.erb
@@ -4,7 +4,14 @@
   </div>
 
   <div class="col-span-3">
-    <%= render "transactions/categories/badge", category: transaction.category %>
+    <% if transaction.marked_as_transfer %>
+      <div class="flex items-center gap-1 text-gray-500 pl-5">
+        <%= lucide_icon "arrow-right-left", class: "w-4 h-4 text-gray-500" %>
+        <p>Transfer</p>
+      </div>
+    <% else %>
+      <%= render "transactions/categories/badge", category: transaction.category %>
+    <% end %>
   </div>
 
   <%= link_to transaction.account.name,
diff --git a/app/views/transactions/_date_group.html.erb b/app/views/transactions/_date_group.html.erb
index c54d5d97..7ec9be4b 100644
--- a/app/views/transactions/_date_group.html.erb
+++ b/app/views/transactions/_date_group.html.erb
@@ -1,17 +1,26 @@
-<%# locals: (date:, transactions:) %>
+<%# locals: (date:, group:) %>
 <div class="bg-gray-25 rounded-xl p-1 w-full" data-bulk-select-target="group">
   <div class="py-2 px-4 flex items-center justify-between font-medium text-xs text-gray-500">
     <div class="flex pl-0.5 items-center gap-4">
       <%= check_box_tag "#{date}_transactions_selection",
-                        class: "maybe-checkbox maybe-checkbox--light",
+                        class: ["maybe-checkbox maybe-checkbox--light", "hidden": group[:transactions].count == 0],
                         id: "selection_transaction_#{date}",
                         data: { action: "bulk-select#toggleGroupSelection" } %>
-      <%= tag.span "#{date.strftime('%b %d, %Y')} · #{transactions.size}" %>
+
+      <%= tag.span "#{date.strftime('%b %d, %Y')} · #{group[:transactions].size + (group[:transfers].size * 2)}" %>
+    </div>
+
+    <div>
+      <% transactions_by_currency = group[:transactions].group_by(&:currency) %>
+      <% transactions_by_currency.each_with_index do |(_currency, transactions), idx| %>
+        <%= tag.span format_money(-transactions.sum(&:amount_money)) %>
+        <%= tag.span "|", class: "mx-2" if idx < transactions_by_currency.count - 1 %>
+      <% end %>
     </div>
 
-    <%= tag.span format_money(-transactions.sum(&:amount_money)) %>
   </div>
   <div class="bg-white shadow-xs rounded-md border border-alpha-black-25 divide-y divide-alpha-black-50">
-    <%= render transactions %>
+    <%= render group[:transactions] %>
+    <%= render group[:transfers] %>
   </div>
 </div>
diff --git a/app/views/transactions/_form.html.erb b/app/views/transactions/_form.html.erb
index 1741b150..2cd52e18 100644
--- a/app/views/transactions/_form.html.erb
+++ b/app/views/transactions/_form.html.erb
@@ -1,9 +1,12 @@
-<%= form_with model: @transaction, data: { turbo: false } do |f| %>
+<%= form_with model: @transaction, data: { turbo_frame: "_top" } do |f| %>
   <section>
     <fieldset class="bg-gray-50 rounded-lg p-1 grid grid-flow-col justify-stretch gap-x-2">
-      <%= radio_tab_tag form: f, name: :nature, value: :expense, label: t(".expense"), icon: "minus-circle", checked: true %>
-      <%= radio_tab_tag form: f, name: :nature, value: :income, label: t(".income"), icon: "plus-circle" %>
-      <%= radio_tab_tag form: f, name: :nature, value: :transfer, label: t(".transfer"), icon: "arrow-right-left", disabled: true %>
+      <%= radio_tab_tag form: f, name: :nature, value: :expense, label: t(".expense"), icon: "minus-circle", checked: params[:nature] == "expense" || params[:nature].nil? %>
+      <%= radio_tab_tag form: f, name: :nature, value: :income, label: t(".income"), icon: "plus-circle", checked: params[:nature] == "income" %>
+      <%= link_to new_transfer_path, data: { turbo_frame: :modal }, class: "flex px-4 py-1 rounded-lg items-center space-x-2 justify-center text-gray-400 group-has-[:checked]:bg-white group-has-[:checked]:text-gray-800 group-has-[:checked]:shadow-sm" do %>
+        <%= lucide_icon "arrow-right-left", class: "w-5 h-5" %>
+        <%= tag.span t(".transfer") %>
+      <% end %>
     </fieldset>
   </section>
 
@@ -11,7 +14,7 @@
     <%= f.text_field :name, label: t(".description"), placeholder: t(".description_placeholder"), required: true %>
     <%= f.collection_select :account_id, Current.family.accounts.alphabetically, :id, :name, { prompt: t(".account_prompt"), label: t(".account") }, required: true %>
     <%= f.money_field :amount_money, label: t(".amount"), required: true %>
-    <%= f.collection_select :category_id, Current.family.transaction_categories.alphabetically, :id, :name, { prompt: t(".category_prompt"), label: t(".category") }, required: true %>
+    <%= f.collection_select :category_id, Current.family.transaction_categories.alphabetically, :id, :name, { prompt: t(".category_prompt"), label: t(".category") } %>
     <%= f.date_field :date, label: t(".date"), required: true, max: Date.today %>
   </section>
 
diff --git a/app/views/transactions/_name.html.erb b/app/views/transactions/_name.html.erb
index 09bc09dd..32891964 100644
--- a/app/views/transactions/_name.html.erb
+++ b/app/views/transactions/_name.html.erb
@@ -9,7 +9,7 @@
     <% else %>
       <%= link_to transaction.name,
                   transaction_path(transaction),
-                  data: { turbo_frame: "drawer" },
+                  data: { turbo_frame: "drawer", turbo_prefetch: false },
                   class: "hover:underline hover:text-gray-800" %>
     <% end %>
   </div>
diff --git a/app/views/transactions/_selection_bar.html.erb b/app/views/transactions/_selection_bar.html.erb
index 34cc0a1f..d03ca5f3 100644
--- a/app/views/transactions/_selection_bar.html.erb
+++ b/app/views/transactions/_selection_bar.html.erb
@@ -8,6 +8,21 @@
   <div class="flex items-center gap-1 text-gray-500">
     <%= turbo_frame_tag "bulk_transaction_edit_drawer" %>
 
+    <%= form_with url: mark_transfers_transactions_path,
+                  builder: ActionView::Helpers::FormBuilder,
+                  scope: "bulk_update",
+                  data: {
+                    turbo_confirm: {
+                      title: t(".mark_transfers"),
+                      body: t(".mark_transfers_message"),
+                      accept: t(".mark_transfers_confirm"),
+                    }
+                  } do |f| %>
+      <button type="button" data-bulk-select-scope-param="bulk_update" data-action="bulk-select#submitBulkRequest" class="p-1.5 group hover:bg-gray-700 flex items-center justify-center rounded-md" title="Mark as transfer">
+        <%= lucide_icon "arrow-right-left", class: "w-5 group-hover:text-white" %>
+      </button>
+    <% end %>
+
     <%= link_to bulk_edit_transactions_path,
                 class: "p-1.5 group hover:bg-gray-700 flex items-center justify-center rounded-md",
                 title: "Edit",
diff --git a/app/views/transactions/_transaction.html.erb b/app/views/transactions/_transaction.html.erb
index 3e04a625..c824cee0 100644
--- a/app/views/transactions/_transaction.html.erb
+++ b/app/views/transactions/_transaction.html.erb
@@ -1,22 +1,41 @@
-<%= turbo_frame_tag dom_id(transaction), class: "grid grid-cols-12 items-center text-gray-900 py-4 text-sm font-medium px-4" do %>
-  <div class="col-span-4 flex items-center gap-4">
+<%= turbo_frame_tag dom_id(transaction), class: "grid grid-cols-12 items-center text-gray-900 text-sm font-medium p-4" do %>
+  <div class="pr-10 flex items-center gap-4 <%= unconfirmed_transfer?(transaction) ? "col-span-10" : "col-span-4" %>">
     <%= check_box_tag dom_id(transaction, "selection"),
                       class: "maybe-checkbox maybe-checkbox--light",
                       data: { id: transaction.id, "bulk-select-target": "row", action: "bulk-select#toggleRowSelection" } %>
 
-    <div class="max-w-full pr-10">
+    <div class="max-w-full">
       <%= render "transactions/name", transaction: transaction %>
     </div>
+
+    <% if unconfirmed_transfer?(transaction) %>
+      <%= form_with url: unmark_transfers_transactions_path, builder: ActionView::Helpers::FormBuilder, class: "flex items-center", data: {
+        turbo_confirm: {
+          title: t(".remove_transfer"),
+          body: t(".remove_transfer_body"),
+          accept: t(".remove_transfer_confirm"),
+        },
+        turbo_frame: "_top"
+      } do |f| %>
+        <%= f.hidden_field "bulk_update[transaction_ids][]", value: transaction.id %>
+        <%= f.button class: "flex items-center justify-center group", title: "Remove transfer" do %>
+          <%= lucide_icon "arrow-left-right", class: "group-hover:hidden text-gray-500 w-4 h-4" %>
+          <%= lucide_icon "unlink", class: "hidden group-hover:inline-block text-gray-900 w-4 h-4" %>
+        <% end %>
+      <% end %>
+    <% end %>
   </div>
 
-  <div class="col-span-3">
-    <%= render "transactions/categories/menu", transaction: transaction %>
-  </div>
+  <% unless unconfirmed_transfer?(transaction) %>
+    <div class="col-span-3">
+      <%= render "transactions/categories/menu", transaction: transaction %>
+    </div>
 
-  <%= link_to transaction.account.name,
-              account_path(transaction.account),
-              data: { turbo_frame: "_top" },
-              class: ["col-span-3 hover:underline"] %>
+    <%= link_to transaction.account.name,
+                account_path(transaction.account),
+                data: { turbo_frame: "_top" },
+                class: ["col-span-3 hover:underline"] %>
+  <% end %>
 
   <div class="col-span-2 ml-auto">
     <%= render "transactions/amount", transaction: transaction %>
diff --git a/app/views/transactions/index.html.erb b/app/views/transactions/index.html.erb
index 61d8115d..23fff412 100644
--- a/app/views/transactions/index.html.erb
+++ b/app/views/transactions/index.html.erb
@@ -25,8 +25,8 @@
         <p class="col-span-2 justify-self-end">amount</p>
       </div>
       <div class="space-y-6">
-        <% @transactions.group_by(&:date).each do |date, transactions| %>
-          <%= render partial: "date_group", locals: { date:, transactions: } %>
+        <% group_transactions_by_date(@transactions).each do |date, group| %>
+          <%= render partial: "date_group", locals: { date:, group: } %>
         <% end %>
       </div>
     <% else %>
diff --git a/app/views/transactions/show.html.erb b/app/views/transactions/show.html.erb
index 53a6a657..6fc355d1 100644
--- a/app/views/transactions/show.html.erb
+++ b/app/views/transactions/show.html.erb
@@ -1,10 +1,16 @@
 <%= drawer do %>
   <div>
     <header class="mb-4 space-y-1">
-      <h3 class="font-medium">
-        <span class="text-2xl"><%= format_money @transaction.amount_money %></span>
-        <span class="text-lg text-gray-500"><%= @transaction.currency %></span>
-      </h3>
+      <div class="flex items-center gap-4">
+        <h3 class="font-medium">
+          <span class="text-2xl"><%= format_money -@transaction.amount_money %></span>
+          <span class="text-lg text-gray-500"><%= @transaction.currency %></span>
+        </h3>
+
+        <% if @transaction.marked_as_transfer %>
+          <%= lucide_icon "arrow-left-right", class: "text-gray-500 mt-1 w-5 h-5" %>
+        <% end %>
+      </div>
 
       <span class="text-sm text-gray-500"><%= @transaction.date.strftime("%A %d %B") %></span>
     </header>
@@ -19,28 +25,20 @@
         <div class="pb-6">
           <%= form_with model: @transaction, html: { data: { controller: "auto-submit-form" } } do |f| %>
             <div class="space-y-2">
+              <%= f.text_field :name, label: t(".name_label"), "data-auto-submit-form-target": "auto" %>
               <%= f.date_field :date, label: t(".date_label"), max: Date.today, "data-auto-submit-form-target": "auto" %>
-              <%= f.collection_select :category_id, Current.family.transaction_categories.alphabetically, :id, :name, { prompt: t(".category_placeholder"), label: t(".category_label"), class: "text-gray-400" }, "data-auto-submit-form-target": "auto" %>
-              <%= f.collection_select :merchant_id, Current.family.transaction_merchants.alphabetically, :id, :name, { prompt: t(".merchant_placeholder"), label: t(".merchant_label"), class: "text-gray-400" }, "data-auto-submit-form-target": "auto" %>
+
+              <% unless @transaction.marked_as_transfer %>
+                <%= f.collection_select :category_id, Current.family.transaction_categories.alphabetically, :id, :name, { prompt: t(".category_placeholder"), label: t(".category_label"), class: "text-gray-400" }, "data-auto-submit-form-target": "auto" %>
+                <%= f.collection_select :merchant_id, Current.family.transaction_merchants.alphabetically, :id, :name, { prompt: t(".merchant_placeholder"), label: t(".merchant_label"), class: "text-gray-400" }, "data-auto-submit-form-target": "auto" %>
+              <% end %>
+
               <%= f.collection_select :account_id, Current.family.accounts.alphabetically, :id, :name, { prompt: t(".account_placeholder"), label: t(".account_label"), class: "text-gray-500" }, { class: "form-field__input cursor-not-allowed text-gray-400", disabled: "disabled" } %>
             </div>
           <% end %>
         </div>
       </details>
 
-      <details class="group space-y-2" open>
-        <summary class="flex list-none items-center justify-between rounded-xl px-3 py-2 text-xs font-medium uppercase text-gray-500 bg-gray-25 focus-visible:outline-none">
-          <h4><%= t(".description") %></h4>
-          <%= lucide_icon "chevron-down", class: "group-open:transform group-open:rotate-180 text-gray-500 w-5" %>
-        </summary>
-
-        <div class="pb-6">
-          <%= form_with model: @transaction, html: { data: { controller: "auto-submit-form" } } do |f| %>
-            <%= f.text_field :name, label: t(".name_label"), "data-auto-submit-form-target": "auto" %>
-          <% end %>
-        </div>
-      </details>
-
       <details class="group space-y-2" open>
         <summary class="flex list-none items-center justify-between rounded-xl px-3 py-2 text-xs font-medium uppercase text-gray-500 bg-gray-25 focus-visible:outline-none">
           <h4><%= t(".additional") %></h4>
@@ -70,8 +68,8 @@
 
         <div class="pb-6">
 
-          <%= form_with model: @transaction, html: { class: "p-3", data: { controller: "auto-submit-form" } } do |f| %>
-            <div class="flex cursor-pointer items-center justify-between">
+          <%= form_with model: @transaction, html: { class: "p-3 space-y-3", data: { controller: "auto-submit-form" } } do |f| %>
+            <div class="flex cursor-pointer items-center gap-2 justify-between">
               <div class="text-sm space-y-1">
                 <h4 class="text-gray-900"><%= t(".exclude_title") %></h4>
                 <p class="text-gray-500"><%= t(".exclude_subtitle") %></p>
@@ -84,18 +82,20 @@
             </div>
           <% end %>
 
-          <div class="flex items-center justify-between gap-2 p-3">
-            <div class="text-sm space-y-1">
-              <h4 class="text-gray-900"><%= t(".delete_title") %></h4>
-              <p class="text-gray-500"><%= t(".delete_subtitle") %></p>
-            </div>
+          <% unless @transaction.transfer? %>
+            <div class="flex items-center justify-between gap-2 p-3">
+              <div class="text-sm space-y-1">
+                <h4 class="text-gray-900"><%= t(".delete_title") %></h4>
+                <p class="text-gray-500"><%= t(".delete_subtitle") %></p>
+              </div>
 
-            <%= button_to t(".delete"),
-                          transaction_path(@transaction),
-                          method: :delete,
-                          class: "rounded-lg px-3 py-2 text-red-500 text-sm font-medium border border-alpha-black-200",
-                          data: { turbo_confirm: true, turbo_frame: "_top" } %>
-          </div>
+              <%= button_to t(".delete"),
+                            transaction_path(@transaction),
+                            method: :delete,
+                            class: "rounded-lg px-3 py-2 text-red-500 text-sm font-medium border border-alpha-black-200",
+                            data: { turbo_confirm: true, turbo_frame: "_top" } %>
+            </div>
+          <% end %>
         </div>
       </details>
     </div>
diff --git a/app/views/transfers/_form.html.erb b/app/views/transfers/_form.html.erb
new file mode 100644
index 00000000..0a8cfcd1
--- /dev/null
+++ b/app/views/transfers/_form.html.erb
@@ -0,0 +1,32 @@
+<%= form_with model: transfer do |f| %>
+  <section>
+    <fieldset class="bg-gray-50 rounded-lg p-1 grid grid-flow-col justify-stretch gap-x-2">
+      <%= link_to new_transaction_path(nature: "expense"), data: { turbo_frame: :modal }, class: "flex px-4 py-1 rounded-lg items-center space-x-2 justify-center text-gray-400" do %>
+        <%= lucide_icon "minus-circle", class: "w-5 h-5" %>
+        <%= tag.span t(".expense") %>
+      <% end %>
+
+      <%= link_to new_transaction_path(nature: "income"), data: { turbo_frame: :modal }, class: "flex px-4 py-1 rounded-lg items-center space-x-2 justify-center text-gray-400" do %>
+        <%= lucide_icon "plus-circle", class: "w-5 h-5" %>
+        <%= tag.span t(".income") %>
+      <% end %>
+
+      <%= tag.div class: "flex px-4 py-1 rounded-lg items-center space-x-2 justify-center text-gray-400 bg-white text-gray-800 shadow-sm" do %>
+        <%= lucide_icon "arrow-right-left", class: "w-5 h-5" %>
+        <%= tag.span t(".transfer") %>
+      <% end %>
+    </fieldset>
+  </section>
+
+  <section class="space-y-2">
+    <%= f.text_field :name, value: transfer.transactions.first&.name, label: t(".description"), placeholder: t(".description_placeholder"), required: true %>
+    <%= f.collection_select :from_account_id, Current.family.accounts.alphabetically, :id, :name, { prompt: t(".select_account"), label: t(".from") }, required: true %>
+    <%= f.collection_select :to_account_id, Current.family.accounts.alphabetically, :id, :name, { prompt: t(".select_account"), label: t(".to") }, required: true %>
+    <%= f.money_field :amount_money, label: t(".amount"), required: true %>
+    <%= f.date_field :date, value: transfer.transactions.first&.date, label: t(".date"), required: true, max: Date.current %>
+  </section>
+
+  <section>
+    <%= f.submit t(".submit") %>
+  </section>
+<% end %>
diff --git a/app/views/transfers/_transfer.html.erb b/app/views/transfers/_transfer.html.erb
new file mode 100644
index 00000000..fae63dae
--- /dev/null
+++ b/app/views/transfers/_transfer.html.erb
@@ -0,0 +1,37 @@
+<%= turbo_frame_tag dom_id(transfer), class: "block" do %>
+  <details class="group flex items-center text-gray-900 p-4 text-sm font-medium">
+    <summary class="flex items-center justify-between">
+      <div class="flex items-center gap-4">
+        <%= button_to transfer_path(transfer),
+                      method: :delete,
+                      class: "flex items-center group/transfer",
+                      data: {
+                        turbo_frame: "_top",
+                        turbo_confirm: {
+                          title: t(".remove_title"),
+                          body: t(".remove_body"),
+                          confirm: t(".remove_confirm")
+                        }
+                      } do %>
+          <%= lucide_icon "arrow-left-right", class: "group-hover/transfer:hidden w-5 h-5 text-gray-500" %>
+          <%= lucide_icon "unlink", class: "group-hover/transfer:inline-block hidden w-5 h-5 text-gray-500" %>
+        <% end %>
+
+        <div class="max-w-full pr-10 select-none">
+          <%= tag.p t(".transfer_name", from_account: transfer.outflow_transaction&.account&.name, to_account: transfer.inflow_transaction&.account&.name) %>
+        </div>
+      </div>
+
+      <%= lucide_icon "chevron-down", class: "group-open:transform group-open:rotate-180 text-gray-500 w-5" %>
+    </summary>
+
+    <div class="pt-2 divide-y divide-alpha-black-200">
+      <% transfer.transactions.each do |transaction| %>
+        <div class="py-3 flex items-center justify-between">
+          <%= render "transactions/name", transaction: transaction %>
+          <%= render "transactions/amount", transaction: transaction %>
+        </div>
+      <% end %>
+    </div>
+  </details>
+<% end %>
diff --git a/app/views/transfers/new.html.erb b/app/views/transfers/new.html.erb
new file mode 100644
index 00000000..fc399358
--- /dev/null
+++ b/app/views/transfers/new.html.erb
@@ -0,0 +1,17 @@
+<%= modal do %>
+  <article class="mx-auto p-4 space-y-4 w-screen max-w-xl">
+    <header class="flex justify-between">
+      <%= tag.h2 t(".title"), class: "font-medium text-xl" %>
+      <%= lucide_icon "x", class: "w-5 h-5 text-gray-500", data: { action: "click->modal#close" } %>
+    </header>
+
+    <% if @transfer.errors.present? %>
+      <div class="text-red-600 flex items-center gap-2">
+        <%= lucide_icon "circle-alert", class: "w-5 h-5" %>
+        <p class="text-sm"><%= @transfer.errors.full_messages.to_sentence %></p>
+      </div>
+    <% end %>
+
+    <%= render "form", transfer: @transfer %>
+  </article>
+<% end %>
diff --git a/config/locales/views/transactions/en.yml b/config/locales/views/transactions/en.yml
index b021bc00..8b5e7e53 100644
--- a/config/locales/views/transactions/en.yml
+++ b/config/locales/views/transactions/en.yml
@@ -89,6 +89,8 @@ en:
       import: Import
     index:
       transaction: transaction
+    mark_transfers:
+      success: Marked as transfer
     merchants:
       create:
         success: New merchant created successfully
@@ -116,6 +118,11 @@ en:
         title: New merchant
       update:
         success: Merchant updated successfully
+    selection_bar:
+      mark_transfers: Mark as transfers?
+      mark_transfers_confirm: Mark as transfers
+      mark_transfers_message: By marking transactions as transfers, they will no longer
+        be included in income or spending calculations.
     show:
       account_label: Account
       account_placeholder: Select an account
@@ -127,7 +134,6 @@ en:
       delete_subtitle: This permanently deletes the transaction, affects your historical
         balances, and cannot be undone.
       delete_title: Delete transaction
-      description: Description
       exclude_subtitle: This excludes the transaction from any in-app features or
         analytics.
       exclude_title: Exclude transaction
@@ -139,5 +145,11 @@ en:
       overview: Overview
       settings: Settings
       tags_label: Select one or more tags
+    transaction:
+      remove_transfer: Remove transfer
+      remove_transfer_body: This will remove the transfer from this transaction
+      remove_transfer_confirm: Confirm
+    unmark_transfers:
+      success: Transfer removed
     update:
       success: Transaction updated successfully
diff --git a/config/locales/views/transfers/en.yml b/config/locales/views/transfers/en.yml
new file mode 100644
index 00000000..79b842a2
--- /dev/null
+++ b/config/locales/views/transfers/en.yml
@@ -0,0 +1,27 @@
+---
+en:
+  transfers:
+    create:
+      success: Transfer created
+    destroy:
+      success: Transfer removed
+    form:
+      amount: Amount
+      date: Date
+      description: Description
+      description_placeholder: Transfer from Checking to Savings
+      expense: Expense
+      from: From
+      income: Income
+      select_account: Select account
+      submit: Create transfer
+      to: To
+      transfer: Transfer
+    new:
+      title: New transfer
+    transfer:
+      remove_body: This will NOT delete the underlying transactions.  It will just
+        remove the transfer.
+      remove_confirm: Confirm
+      remove_title: Remove transfer?
+      transfer_name: Transfer from %{from_account} to %{to_account}
diff --git a/config/routes.rb b/config/routes.rb
index feb262e6..b38ddbb6 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -46,6 +46,8 @@ Rails.application.routes.draw do
       post "bulk_delete"
       get "bulk_edit"
       post "bulk_update"
+      post "mark_transfers"
+      post "unmark_transfers"
 
       scope module: :transactions, as: :transaction do
         resources :rows, only: %i[ show update ]
@@ -63,6 +65,8 @@ Rails.application.routes.draw do
     end
   end
 
+  resources :transfers, only: %i[ new create destroy ]
+
   resources :accounts, shallow: true do
     get :summary, on: :collection
     get :list, on: :collection
diff --git a/db/migrate/20240614120946_create_transfers.rb b/db/migrate/20240614120946_create_transfers.rb
new file mode 100644
index 00000000..d53ad290
--- /dev/null
+++ b/db/migrate/20240614120946_create_transfers.rb
@@ -0,0 +1,7 @@
+class CreateTransfers < ActiveRecord::Migration[7.2]
+  def change
+    create_table :transfers, id: :uuid do |t|
+      t.timestamps
+    end
+  end
+end
diff --git a/db/migrate/20240614121110_add_transfer_fields_to_transaction.rb b/db/migrate/20240614121110_add_transfer_fields_to_transaction.rb
new file mode 100644
index 00000000..ec91f908
--- /dev/null
+++ b/db/migrate/20240614121110_add_transfer_fields_to_transaction.rb
@@ -0,0 +1,8 @@
+class AddTransferFieldsToTransaction < ActiveRecord::Migration[7.2]
+  def change
+    change_table :transactions do |t|
+      t.references :transfer, foreign_key: true, type: :uuid
+      t.boolean :marked_as_transfer, default: false, null: false
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 56a0d4c0..be01a8cc 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.2].define(version: 2024_06_12_164944) do
+ActiveRecord::Schema[7.2].define(version: 2024_06_14_121110) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "pgcrypto"
   enable_extension "plpgsql"
@@ -87,7 +87,7 @@ ActiveRecord::Schema[7.2].define(version: 2024_06_12_164944) do
     t.uuid "accountable_id"
     t.decimal "balance", precision: 19, scale: 4, default: "0.0"
     t.string "currency", default: "USD"
-    t.virtual "classification", type: :string, as: "\nCASE\n    WHEN ((accountable_type)::text = ANY (ARRAY[('Account::Loan'::character varying)::text, ('Account::Credit'::character varying)::text, ('Account::OtherLiability'::character varying)::text])) THEN 'liability'::text\n    ELSE 'asset'::text\nEND", stored: true
+    t.virtual "classification", type: :string, as: "\nCASE\n    WHEN ((accountable_type)::text = ANY ((ARRAY['Account::Loan'::character varying, 'Account::Credit'::character varying, 'Account::OtherLiability'::character varying])::text[])) THEN 'liability'::text\n    ELSE 'asset'::text\nEND", stored: true
     t.boolean "is_active", default: true, null: false
     t.enum "status", default: "ok", null: false, enum_type: "account_status"
     t.jsonb "sync_warnings", default: [], null: false
@@ -310,9 +310,17 @@ ActiveRecord::Schema[7.2].define(version: 2024_06_12_164944) do
     t.boolean "excluded", default: false
     t.text "notes"
     t.uuid "merchant_id"
+    t.uuid "transfer_id"
+    t.boolean "marked_as_transfer", default: false, null: false
     t.index ["account_id"], name: "index_transactions_on_account_id"
     t.index ["category_id"], name: "index_transactions_on_category_id"
     t.index ["merchant_id"], name: "index_transactions_on_merchant_id"
+    t.index ["transfer_id"], name: "index_transactions_on_transfer_id"
+  end
+
+  create_table "transfers", id: :uuid, default: -> { "gen_random_uuid()" }, force: :cascade do |t|
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
   end
 
   create_table "users", id: :uuid, default: -> { "gen_random_uuid()" }, force: :cascade do |t|
@@ -357,6 +365,7 @@ ActiveRecord::Schema[7.2].define(version: 2024_06_12_164944) do
   add_foreign_key "transactions", "accounts", on_delete: :cascade
   add_foreign_key "transactions", "transaction_categories", column: "category_id", on_delete: :nullify
   add_foreign_key "transactions", "transaction_merchants", column: "merchant_id"
+  add_foreign_key "transactions", "transfers"
   add_foreign_key "users", "families"
   add_foreign_key "valuations", "accounts", on_delete: :cascade
 end
diff --git a/test/controllers/transactions_controller_test.rb b/test/controllers/transactions_controller_test.rb
index 6b36ab52..57feedcc 100644
--- a/test/controllers/transactions_controller_test.rb
+++ b/test/controllers/transactions_controller_test.rb
@@ -4,7 +4,7 @@ class TransactionsControllerTest < ActionDispatch::IntegrationTest
   setup do
     sign_in @user = users(:family_admin)
     @transaction = transactions(:checking_one)
-    @recent_transactions = @user.family.transactions.ordered.limit(20).to_a
+    @recent_transactions = @user.family.transactions.ordered.where(transfer_id: nil).limit(20).to_a
   end
 
   test "should get paginated index with most recent transactions first" do
@@ -18,7 +18,7 @@ class TransactionsControllerTest < ActionDispatch::IntegrationTest
 
   test "transaction count represents filtered total" do
     get transactions_url
-    assert_dom "#total-transactions", count: 1, text: @user.family.transactions.count.to_s
+    assert_dom "#total-transactions", count: 1, text: @user.family.transactions.select { |t| t.currency == "USD" }.count.to_s
 
     new_transaction = @user.family.accounts.first.transactions.create! \
       name: "Transaction to search for",
@@ -42,7 +42,7 @@ class TransactionsControllerTest < ActionDispatch::IntegrationTest
   end
 
   test "loads last page when page is out of range" do
-    user_oldest_transaction = @user.family.transactions.ordered.last
+    user_oldest_transaction = @user.family.transactions.ordered.reject(&:transfer?).last
     get transactions_url(page: 9999999999)
 
     assert_response :success
diff --git a/test/controllers/transfers_controller_test.rb b/test/controllers/transfers_controller_test.rb
new file mode 100644
index 00000000..4a139f67
--- /dev/null
+++ b/test/controllers/transfers_controller_test.rb
@@ -0,0 +1,33 @@
+require "test_helper"
+
+class TransfersControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    sign_in users(:family_admin)
+  end
+
+  test "should get new" do
+    get new_transfer_url
+    assert_response :success
+  end
+
+  test "can create transfers" do
+    assert_difference "Transfer.count", 1 do
+      post transfers_url, params: {
+        transfer: {
+          from_account_id: accounts(:checking).id,
+          to_account_id: accounts(:savings).id,
+          date: Date.current,
+          amount: 100,
+          currency: "USD",
+          name: "Test Transfer"
+        }
+      }
+    end
+  end
+
+  test "can destroy transfer" do
+    assert_difference -> { Transfer.count } => -1, -> { Transaction.count } => 0 do
+      delete transfer_url(transfers(:credit_card_payment))
+    end
+  end
+end
diff --git a/test/fixtures/account/credits.yml b/test/fixtures/account/credits.yml
index 4e67ab5c..1ad8c478 100644
--- a/test/fixtures/account/credits.yml
+++ b/test/fixtures/account/credits.yml
@@ -1,2 +1 @@
-one:
-  id: "123e4567-e89b-12d3-a456-426614174003"
+credit_one: { }
diff --git a/test/fixtures/account/cryptos.yml b/test/fixtures/account/cryptos.yml
index 1f0df1da..e0553ab0 100644
--- a/test/fixtures/account/cryptos.yml
+++ b/test/fixtures/account/cryptos.yml
@@ -1,11 +1 @@
-# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
-
-# This model initially had no columns defined. If you add columns to the
-# model remove the "{}" from the fixture names and add the columns immediately
-# below each fixture, per the syntax in the comments below
-#
-# one: {}
-# column: value
-#
-# two: {}
-# column: value
+one: { }
\ No newline at end of file
diff --git a/test/fixtures/account/depositories.yml b/test/fixtures/account/depositories.yml
index d24bbbb9..ff07aeab 100644
--- a/test/fixtures/account/depositories.yml
+++ b/test/fixtures/account/depositories.yml
@@ -1,8 +1,4 @@
-checking:
-  id: "123e4567-e89b-12d3-a456-426614174000"
-savings:
-  id: "123e4567-e89b-12d3-a456-426614174001"
-eur_checking:
-  id: "123e4567-e89b-12d3-a456-426614174004"
-multi_currency:
-  id: "123e4567-e89b-12d3-a456-426614174005"
+depository_checking: { }
+depository_savings: { }
+depository_eur_checking: { }
+depository_multi_currency: { }
diff --git a/test/fixtures/account/expected_balances.csv b/test/fixtures/account/expected_balances.csv
deleted file mode 100644
index c72f02c4..00000000
--- a/test/fixtures/account/expected_balances.csv
+++ /dev/null
@@ -1,32 +0,0 @@
-date_offset,collectable,checking,savings_with_valuation_overrides,credit_card,eur_checking_eur,eur_checking_usd,multi_currency
--30,400,4000,21250,1040,11850,12947.31,10721.26
--29,400,3985,21750,940,12050,13182.7,10921.26
--28,400,3985,21750,940,12050,13194.75,10921.26
--27,400,3985,21750,940,12050,13132.09,10921.26
--26,400,3985,21750,940,12050,13083.89,10921.26
--25,400,3985,21000,940,12050,13081.48,10921.26
--24,400,3985,21000,940,12050,13062.2,10921.26
--23,400,3985,21000,940,12050,13022.435,10921.26
--22,400,5060,21000,940,12050,13060.995,10921.26
--21,400,5060,21000,940,12050,13068.225,10921.26
--20,400,5060,21000,940,12050,13079.07,10921.26
--19,400,5060,21000,940,11950,12932.29,10813.04
--18,400,5060,19000,940,11950,12934.68,10813.04
--17,400,5060,19000,940,11950,12927.51,10813.04
--16,400,5060,19000,940,11950,12916.755,10813.04
--15,400,5040,19000,960,11950,12882.1,10813.04
--14,400,5040,19000,960,11950,12879.71,10813.04
--13,400,5040,19000,960,11950,12873.735,10813.04
--12,700,5010,19500,990,11950,12821.155,10813.04
--11,700,5010,19500,990,11950,12797.255,10813.04
--10,700,5010,19500,990,11950,12873.735,10813.04
--9,700,5010,19500,990,12000,12939.6,10863.04
--8,700,5010,19500,990,12000,12933.6,10863.04
--7,700,5010,19500,990,12000,12928.8,10863.04
--6,700,5010,19500,990,12000,12906,10863.04
--5,700,5000,19700,1000,12000,12891.6,10863.04
--4,550,5000,19700,1000,12000,12945.6,10000
--3,550,5000,20500,1000,12000,13046.4,10000
--2,550,5000,20500,1000,12000,12982.8,10000
--1,550,5000,20500,1000,12000,13014,10000
-0,550,5000,20500,1000,12000,13000.8,10000
\ No newline at end of file
diff --git a/test/fixtures/account/investments.yml b/test/fixtures/account/investments.yml
index e69de29b..10ecb60d 100644
--- a/test/fixtures/account/investments.yml
+++ b/test/fixtures/account/investments.yml
@@ -0,0 +1 @@
+investment_brokerage: { }
diff --git a/test/fixtures/account/loans.yml b/test/fixtures/account/loans.yml
index e69de29b..6043e466 100644
--- a/test/fixtures/account/loans.yml
+++ b/test/fixtures/account/loans.yml
@@ -0,0 +1 @@
+loan_mortgage: { }
diff --git a/test/fixtures/account/other_assets.yml b/test/fixtures/account/other_assets.yml
index 2734e1b0..74674e8c 100644
--- a/test/fixtures/account/other_assets.yml
+++ b/test/fixtures/account/other_assets.yml
@@ -1,2 +1,3 @@
-one:
-  id: "123e4567-e89b-12d3-a456-426614174002"
+other_asset_collectable: { }
+
+
diff --git a/test/fixtures/account/other_liabilities.yml b/test/fixtures/account/other_liabilities.yml
index e69de29b..08028f97 100644
--- a/test/fixtures/account/other_liabilities.yml
+++ b/test/fixtures/account/other_liabilities.yml
@@ -0,0 +1 @@
+other_asset_iou: { }
diff --git a/test/fixtures/account/properties.yml b/test/fixtures/account/properties.yml
index e69de29b..c6026df2 100644
--- a/test/fixtures/account/properties.yml
+++ b/test/fixtures/account/properties.yml
@@ -0,0 +1 @@
+property_house: { }
diff --git a/test/fixtures/account/vehicles.yml b/test/fixtures/account/vehicles.yml
index e69de29b..a0ea340e 100644
--- a/test/fixtures/account/vehicles.yml
+++ b/test/fixtures/account/vehicles.yml
@@ -0,0 +1 @@
+vehicle_honda_accord: { }
diff --git a/test/fixtures/account_balances.yml b/test/fixtures/account_balances.yml
deleted file mode 100644
index 99798f29..00000000
--- a/test/fixtures/account_balances.yml
+++ /dev/null
@@ -1,13 +0,0 @@
-# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
-
-# one:
-#   account: generic
-#   date: 2024-02-12
-#   balance: 9.99
-#   currency: MyString
-
-# two:
-#   account: generic
-#   date: 2024-02-13
-#   balance: 9.99
-#   currency: MyString
diff --git a/test/fixtures/accounts.yml b/test/fixtures/accounts.yml
index 1859f8d5..bbb96c0f 100644
--- a/test/fixtures/accounts.yml
+++ b/test/fixtures/accounts.yml
@@ -1,36 +1,39 @@
-# Account with only valuations
 collectable:
   family: dylan_family
   name: Collectable Account
   balance: 550
   accountable_type: Account::OtherAsset
-  accountable_id: "123e4567-e89b-12d3-a456-426614174002"
+  accountable: other_asset_collectable
+
+iou:
+  family: dylan_family
+  name: IOU (personal debt to friend)
+  balance: 200
+  accountable_type: Account::OtherLiability
+  accountable: other_liability_iou
 
-# Account with only transactions
 checking:
   family: dylan_family
   name: Checking Account
   balance: 5000
   accountable_type: Account::Depository
-  accountable_id: "123e4567-e89b-12d3-a456-426614174000"
+  accountable: depository_checking
   institution: chase
 
-# Account with both transactions and valuations
-savings_with_valuation_overrides:
+savings:
   family: dylan_family
   name: Savings account with valuation overrides
-  balance: 20000
+  balance: 19700
   accountable_type: Account::Depository
-  accountable_id: "123e4567-e89b-12d3-a456-426614174001"
+  accountable: depository_savings
   institution: chase
 
-# Liability account
 credit_card:
   family: dylan_family
   name: Credit Card
   balance: 1000
   accountable_type: Account::Credit
-  accountable_id: "123e4567-e89b-12d3-a456-426614174003"
+  accountable: credit_one
   institution: chase
 
 eur_checking:
@@ -39,7 +42,7 @@ eur_checking:
   currency: EUR
   balance: 12000
   accountable_type: Account::Depository
-  accountable_id: "123e4567-e89b-12d3-a456-426614174004"
+  accountable: depository_eur_checking
   institution: revolut
 
 # Multi-currency account (e.g. Wise, Revolut, etc.)
@@ -47,7 +50,39 @@ multi_currency:
   family: dylan_family
   name: Multi Currency Account
   currency: USD # multi-currency accounts still have a "primary" currency
-  balance: 10000
+  balance: 9467
   accountable_type: Account::Depository
-  accountable_id: "123e4567-e89b-12d3-a456-426614174005"
+  accountable: depository_multi_currency
   institution: revolut
+
+brokerage:
+  family: dylan_family
+  name: Robinhood Brokerage Account
+  currency: USD
+  balance: 10000
+  accountable_type: Account::Investment
+  accountable: investment_brokerage
+
+mortgage_loan:
+  family: dylan_family
+  name: Mortgage Loan
+  currency: USD
+  balance: 500000
+  accountable_type: Account::Loan
+  accountable: loan_mortgage
+
+house:
+  family: dylan_family
+  name: 123 Maybe Court
+  currency: USD
+  balance: 550000
+  accountable_type: Account::Property
+  accountable: property_house
+
+car:
+  family: dylan_family
+  name: Honda Accord
+  currency: USD
+  balance: 18000
+  accountable_type: Account::Vehicle
+  accountable: vehicle_honda_accord
diff --git a/test/fixtures/exchange_rates.yml b/test/fixtures/exchange_rates.yml
index 9b367421..533d16cf 100644
--- a/test/fixtures/exchange_rates.yml
+++ b/test/fixtures/exchange_rates.yml
@@ -1,308 +1,381 @@
+day_31_ago_eur_to_usd:
+  base_currency: EUR
+  converted_currency: USD
+  rate: 1.0986
+  date: <%= 31.days.ago.to_date %>
+
 day_30_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0926
   date: <%= 30.days.ago.to_date %>
+
 day_29_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.094
   date: <%= 29.days.ago.to_date %>
+
 day_28_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.095
   date: <%= 28.days.ago.to_date %>
+
 day_27_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0898
   date: <%= 27.days.ago.to_date %>
+
 day_26_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0858
   date: <%= 26.days.ago.to_date %>
+
 day_25_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0856
   date: <%= 25.days.ago.to_date %>
+
 day_24_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.084
   date: <%= 24.days.ago.to_date %>
+
 day_23_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0807
   date: <%= 23.days.ago.to_date %>
+
 day_22_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0839
   date: <%= 22.days.ago.to_date %>
+
 day_21_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0845
   date: <%= 21.days.ago.to_date %>
+
 day_20_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0854
   date: <%= 20.days.ago.to_date %>
+
 day_19_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0822
   date: <%= 19.days.ago.to_date %>
+
 day_18_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0824
   date: <%= 18.days.ago.to_date %>
+
 day_17_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0818
   date: <%= 17.days.ago.to_date %>
+
 day_16_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0809
   date: <%= 16.days.ago.to_date %>
+
 day_15_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.078
   date: <%= 15.days.ago.to_date %>
+
 day_14_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0778
   date: <%= 14.days.ago.to_date %>
+
 day_13_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0773
   date: <%= 13.days.ago.to_date %>
+
 day_12_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0729
   date: <%= 12.days.ago.to_date %>
+
 day_11_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0709
   date: <%= 11.days.ago.to_date %>
+
 day_10_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0773
   date: <%= 10.days.ago.to_date %>
+
 day_9_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0783
   date: <%= 9.days.ago.to_date %>
+
 day_8_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0778
   date: <%= 8.days.ago.to_date %>
+
 day_7_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0774
   date: <%= 7.days.ago.to_date %>
+
 day_6_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0755
   date: <%= 6.days.ago.to_date %>
+
 day_5_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0743
   date: <%= 5.days.ago.to_date %>
+
 day_4_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0788
   date: <%= 4.days.ago.to_date %>
+
 day_3_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0872
   date: <%= 3.days.ago.to_date %>
+
 day_2_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0819
   date: <%= 2.days.ago.to_date %>
+
 day_1_ago_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0845
   date: <%= 1.days.ago.to_date %>
+
 today_eur_to_usd:
   base_currency: EUR
   converted_currency: USD
   rate: 1.0834
   date: <%= Date.current %>
+
+day_31_ago_usd_to_eur:
+  base_currency: USD
+  converted_currency: EUR
+  rate: 0.9279
+  date: <%= 31.days.ago.to_date %>
+
 day_30_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9179
   date: <%= 30.days.ago.to_date %>
+
 day_29_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9154
   date: <%= 29.days.ago.to_date %>
+
 day_28_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9107
   date: <%= 28.days.ago.to_date %>
+
 day_27_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9139
   date: <%= 27.days.ago.to_date %>
+
 day_26_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9082
   date: <%= 26.days.ago.to_date %>
+
 day_25_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9077
   date: <%= 25.days.ago.to_date %>
+
 day_24_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9054
   date: <%= 24.days.ago.to_date %>
+
 day_23_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9004
   date: <%= 23.days.ago.to_date %>
+
 day_22_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9040
   date: <%= 22.days.ago.to_date %>
+
 day_21_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9060
   date: <%= 21.days.ago.to_date %>
+
 day_20_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9052
   date: <%= 20.days.ago.to_date %>
+
 day_19_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9139
   date: <%= 19.days.ago.to_date %>
+
 day_18_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9155
   date: <%= 18.days.ago.to_date %>
+
 day_17_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9135
   date: <%= 17.days.ago.to_date %>
+
 day_16_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9141
   date: <%= 16.days.ago.to_date %>
+
 day_15_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9131
   date: <%= 15.days.ago.to_date %>
+
 day_14_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9147
   date: <%= 14.days.ago.to_date %>
+
 day_13_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9112
   date: <%= 13.days.ago.to_date %>
+
 day_12_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9115
   date: <%= 12.days.ago.to_date %>
+
 day_11_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9132
   date: <%= 11.days.ago.to_date %>
+
 day_10_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9130
   date: <%= 10.days.ago.to_date %>
+
 day_9_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9192
   date: <%= 9.days.ago.to_date %>
+
 day_8_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9188
   date: <%= 8.days.ago.to_date %>
+
 day_7_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9194
   date: <%= 7.days.ago.to_date %>
+
 day_6_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9177
   date: <%= 6.days.ago.to_date %>
+
 day_5_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9187
   date: <%= 5.days.ago.to_date %>
+
 day_4_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9213
   date: <%= 4.days.ago.to_date %>
+
 day_3_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9186
   date: <%= 3.days.ago.to_date %>
+
 day_2_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9218
   date: <%= 2.days.ago.to_date %>
+
 day_1_ago_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
   rate: 0.9213
   date: <%= 1.days.ago.to_date %>
+
 today_usd_to_eur:
   base_currency: USD
   converted_currency: EUR
diff --git a/test/fixtures/family/expected_snapshots.csv b/test/fixtures/family/expected_snapshots.csv
deleted file mode 100644
index fb4a6b01..00000000
--- a/test/fixtures/family/expected_snapshots.csv
+++ /dev/null
@@ -1,32 +0,0 @@
-date_offset,net_worth,assets,liabilities,depositories,investments,loans,credits,properties,vehicles,other_assets,other_liabilities,spending,income,rolling_spend,rolling_income,savings_rate
--30,48278.57,49318.57,1040.00,48918.57,0.00,0.00,1040.00,0.00,0.00,400.00,0.00,0,0,0,0,0
--29,49298.96,50238.96,940.00,49838.96,0.00,0.00,940.00,0.00,0.00,400.00,0.00,15,1018.8,15,1018.8,0.9852767962
--28,49311.01,50251.01,940.00,49851.01,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,1018.8,0.9852767962
--27,49248.35,50188.35,940.00,49788.35,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,1018.8,0.9852767962
--26,49200.15,50140.15,940.00,49740.15,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,1018.8,0.9852767962
--25,48447.74,49387.74,940.00,48987.74,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,1018.8,0.9852767962
--24,48428.46,49368.46,940.00,48968.46,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,1018.8,0.9852767962
--23,48388.70,49328.70,940.00,48928.70,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,1018.8,0.9852767962
--22,49502.26,50442.26,940.00,50042.26,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,1075,15,2093.8,0.992835992
--21,49509.49,50449.49,940.00,50049.49,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,2093.8,0.992835992
--20,49520.33,50460.33,940.00,50060.33,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,15,2093.8,0.992835992
--19,49265.33,50205.33,940.00,49805.33,0.00,0.00,940.00,0.00,0.00,400.00,0.00,216.44,0,231.44,2093.8,0.8894641322
--18,47267.72,48207.72,940.00,47807.72,0.00,0.00,940.00,0.00,0.00,400.00,0.00,2000,0,2231.44,2093.8,-0.06573693763
--17,47260.55,48200.55,940.00,47800.55,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,2231.44,2093.8,-0.06573693763
--16,47249.80,48189.80,940.00,47789.80,0.00,0.00,940.00,0.00,0.00,400.00,0.00,0,0,2231.44,2093.8,-0.06573693763
--15,47175.14,48135.14,960.00,47735.14,0.00,0.00,960.00,0.00,0.00,400.00,0.00,40,0,2271.44,2093.8,-0.08484095902
--14,47172.75,48132.75,960.00,47732.75,0.00,0.00,960.00,0.00,0.00,400.00,0.00,0,0,2271.44,2093.8,-0.08484095902
--13,47166.78,48126.78,960.00,47726.78,0.00,0.00,960.00,0.00,0.00,400.00,0.00,0,0,2271.44,2093.8,-0.08484095902
--12,47854.20,48844.20,990.00,48144.20,0.00,0.00,990.00,0.00,0.00,700.00,0.00,60,50,2331.44,2143.8,-0.08752682153
--11,47830.30,48820.30,990.00,48120.30,0.00,0.00,990.00,0.00,0.00,700.00,0.00,0,0,2331.44,2143.8,-0.08752682153
--10,47906.78,48896.78,990.00,48196.78,0.00,0.00,990.00,0.00,0.00,700.00,0.00,0,0,2331.44,2143.8,-0.08752682153
--9,48022.64,49012.64,990.00,48312.64,0.00,0.00,990.00,0.00,0.00,700.00,0.00,0,103.915,2331.44,2247.715,-0.03724893948
--8,48016.64,49006.64,990.00,48306.64,0.00,0.00,990.00,0.00,0.00,700.00,0.00,0,0,2331.44,2247.715,-0.03724893948
--7,48011.84,49001.84,990.00,48301.84,0.00,0.00,990.00,0.00,0.00,700.00,0.00,0,0,2331.44,2247.715,-0.03724893948
--6,47989.04,48979.04,990.00,48279.04,0.00,0.00,990.00,0.00,0.00,700.00,0.00,0,0,2331.44,2247.715,-0.03724893948
--5,48154.64,49154.64,1000.00,48454.64,0.00,0.00,1000.00,0.00,0.00,700.00,0.00,20,200,2351.44,2447.715,0.03933260204
--4,47195.60,48195.60,1000.00,47645.60,0.00,0.00,1000.00,0.00,0.00,550.00,0.00,863.04,0,3214.48,2447.715,-0.3132574667
--3,48096.40,49096.40,1000.00,48546.40,0.00,0.00,1000.00,0.00,0.00,550.00,0.00,0,0,3214.48,2447.715,-0.3132574667
--2,48032.80,49032.80,1000.00,48482.80,0.00,0.00,1000.00,0.00,0.00,550.00,0.00,0,0,3214.48,2447.715,-0.3132574667
--1,48064.00,49064.00,1000.00,48514.00,0.00,0.00,1000.00,0.00,0.00,550.00,0.00,0,0,3214.48,2447.715,-0.3132574667
-0,48050.80,49050.80,1000.00,48514.00,0.00,0.00,1000.00,0.00,0.00,550.00,0.00,0,0,3214.48,2447.715,-0.3132574667
\ No newline at end of file
diff --git a/test/fixtures/files/.keep b/test/fixtures/files/.keep
deleted file mode 100644
index e69de29b..00000000
diff --git a/test/fixtures/files/expected_family_snapshots.csv b/test/fixtures/files/expected_family_snapshots.csv
new file mode 100644
index 00000000..6b0667e2
--- /dev/null
+++ b/test/fixtures/files/expected_family_snapshots.csv
@@ -0,0 +1,33 @@
+date_offset,collectable,iou,checking,credit_card,savings,eur_checking_eur,eur_checking_usd,multi_currency,brokerage,mortgage_loan,house,car,net_worth,assets,liabilities,depositories,investments,loans,credits,properties,vehicles,other_assets,other_liabilities,spending,income,rolling_spend,rolling_income,savings_rate
+31,400.00,200.00,4950.00,1040.00,20700.00,11850.00,13018.41,10200.00,10000.00,500000.00,550000.00,18000.00,126028.41,627268.41,501240.00,48868.41,10000.00,500000.00,1040.00,550000.00,18000.00,400.00,200.00,0.00,0.00,0.00,0.00,0.0000
+30,400.00,200.00,4100.00,940.00,20950.00,12050.00,13165.83,10200.00,10000.00,500000.00,550000.00,18000.00,125675.83,626815.83,501140.00,48415.83,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,218.52,0.00,218.52,1.0000
+29,400.00,200.00,3985.00,940.00,21450.00,12050.00,13182.70,10400.00,10000.00,500000.00,550000.00,18000.00,126277.70,627417.70,501140.00,49017.70,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,15.00,700.00,15.00,918.52,0.9837
+28,400.00,200.00,3985.00,940.00,21450.00,12050.00,13194.75,10400.00,10000.00,500000.00,550000.00,18000.00,126289.75,627429.75,501140.00,49029.75,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,918.52,0.9837
+27,400.00,200.00,3985.00,940.00,21450.00,12050.00,13132.09,10400.00,10000.00,500000.00,550000.00,18000.00,126227.09,627367.09,501140.00,48967.09,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,918.52,0.9837
+26,400.00,200.00,3985.00,940.00,21450.00,12050.00,13083.89,10400.00,10000.00,500000.00,550000.00,18000.00,126178.89,627318.89,501140.00,48918.89,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,918.52,0.9837
+25,400.00,200.00,3985.00,940.00,21000.00,12050.00,13081.48,10400.00,10000.00,500000.00,550000.00,18000.00,125726.48,626866.48,501140.00,48466.48,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,918.52,0.9837
+24,400.00,200.00,3985.00,940.00,21000.00,12050.00,13062.20,10400.00,10000.00,500000.00,550000.00,18000.00,125707.20,626847.20,501140.00,48447.20,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,918.52,0.9837
+23,400.00,200.00,3985.00,940.00,21000.00,12050.00,13022.44,10400.00,10000.00,500000.00,550000.00,18000.00,125667.44,626807.44,501140.00,48407.44,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,918.52,0.9837
+22,400.00,200.00,5060.00,940.00,21000.00,12050.00,13061.00,10400.00,10000.00,500000.00,550000.00,18000.00,126781.00,627921.00,501140.00,49521.00,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,1075.00,15.00,1993.52,0.9925
+21,400.00,200.00,5060.00,940.00,21000.00,12050.00,13068.23,10400.00,10000.00,500000.00,550000.00,18000.00,126788.23,627928.23,501140.00,49528.23,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,1993.52,0.9925
+20,400.00,200.00,5060.00,940.00,21000.00,12050.00,13079.07,10400.00,10000.00,500000.00,550000.00,18000.00,126799.07,627939.07,501140.00,49539.07,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,15.00,1993.52,0.9925
+19,400.00,200.00,5060.00,940.00,21000.00,11950.00,12932.29,10280.04,10000.00,500000.00,550000.00,18000.00,126532.33,627672.33,501140.00,49272.33,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,228.18,0.00,243.18,1993.52,0.8780
+18,400.00,200.00,5060.00,940.00,19000.00,11950.00,12934.68,10280.04,10000.00,500000.00,550000.00,18000.00,124534.72,625674.72,501140.00,47274.72,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,2000.00,0.00,2243.18,1993.52,-0.1252
+17,400.00,200.00,5060.00,940.00,19000.00,11950.00,12927.51,10280.04,10000.00,500000.00,550000.00,18000.00,124527.55,625667.55,501140.00,47267.55,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,2243.18,1993.52,-0.1252
+16,400.00,200.00,5060.00,940.00,19000.00,11950.00,12916.76,10280.04,10000.00,500000.00,550000.00,18000.00,124516.79,625656.79,501140.00,47256.79,10000.00,500000.00,940.00,550000.00,18000.00,400.00,200.00,0.00,0.00,2243.18,1993.52,-0.1252
+15,400.00,200.00,5040.00,960.00,19000.00,11950.00,12882.10,10280.04,10000.00,500000.00,550000.00,18000.00,124442.14,625602.14,501160.00,47202.14,10000.00,500000.00,960.00,550000.00,18000.00,400.00,200.00,40.00,0.00,2283.18,1993.52,-0.1453
+14,400.00,200.00,5040.00,960.00,19000.00,11950.00,12879.71,10280.04,10000.00,500000.00,550000.00,18000.00,124439.75,625599.75,501160.00,47199.75,10000.00,500000.00,960.00,550000.00,18000.00,400.00,200.00,0.00,0.00,2283.18,1993.52,-0.1453
+13,400.00,200.00,5040.00,960.00,19000.00,11950.00,12873.74,10280.04,10000.00,500000.00,550000.00,18000.00,124433.77,625593.77,501160.00,47193.77,10000.00,500000.00,960.00,550000.00,18000.00,400.00,200.00,0.00,0.00,2283.18,1993.52,-0.1453
+12,700.00,200.00,5010.00,990.00,19500.00,11950.00,12821.16,10280.04,10000.00,500000.00,550000.00,18000.00,125121.19,626311.19,501190.00,47611.19,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,60.00,50.00,2343.18,2043.52,-0.1466
+11,700.00,200.00,5010.00,990.00,19500.00,11950.00,12797.26,10280.04,10000.00,500000.00,550000.00,18000.00,125097.29,626287.29,501190.00,47587.29,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,0.00,0.00,2343.18,2043.52,-0.1466
+10,700.00,200.00,5010.00,990.00,19500.00,11950.00,12873.74,10280.04,10000.00,500000.00,550000.00,18000.00,125173.77,626363.77,501190.00,47663.77,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,0.00,0.00,2343.18,2043.52,-0.1466
+9,700.00,200.00,5010.00,990.00,19500.00,12000.00,12939.60,10330.04,10000.00,500000.00,550000.00,18000.00,125289.64,626479.64,501190.00,47779.64,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,0.00,103.92,2343.18,2147.44,-0.0912
+8,700.00,200.00,5010.00,990.00,19500.00,12000.00,12933.60,10330.04,10000.00,500000.00,550000.00,18000.00,125283.64,626473.64,501190.00,47773.64,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,0.00,0.00,2343.18,2147.44,-0.0912
+7,700.00,200.00,5010.00,990.00,19500.00,12000.00,12928.80,10330.04,10000.00,500000.00,550000.00,18000.00,125278.84,626468.84,501190.00,47768.84,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,0.00,0.00,2343.18,2147.44,-0.0912
+6,700.00,200.00,5010.00,990.00,19500.00,12000.00,12906.00,10330.04,10000.00,500000.00,550000.00,18000.00,125256.04,626446.04,501190.00,47746.04,10000.00,500000.00,990.00,550000.00,18000.00,700.00,200.00,0.00,0.00,2343.18,2147.44,-0.0912
+5,700.00,200.00,5000.00,1000.00,19700.00,12000.00,12891.60,10330.04,10000.00,500000.00,550000.00,18000.00,125421.64,626621.64,501200.00,47921.64,10000.00,500000.00,1000.00,550000.00,18000.00,700.00,200.00,20.00,200.00,2363.18,2347.44,-0.0067
+4,550.00,200.00,5000.00,1000.00,19700.00,12000.00,12945.60,9467.00,10000.00,500000.00,550000.00,18000.00,124462.60,625662.60,501200.00,47112.60,10000.00,500000.00,1000.00,550000.00,18000.00,550.00,200.00,863.04,0.00,3226.22,2347.44,-0.3744
+3,550.00,200.00,5000.00,1000.00,19700.00,12000.00,13046.40,9467.00,10000.00,500000.00,550000.00,18000.00,124563.40,625763.40,501200.00,47213.40,10000.00,500000.00,1000.00,550000.00,18000.00,550.00,200.00,0.00,0.00,3226.22,2347.44,-0.3744
+2,550.00,200.00,5000.00,1000.00,19700.00,12000.00,12982.80,9467.00,10000.00,500000.00,550000.00,18000.00,124499.80,625699.80,501200.00,47149.80,10000.00,500000.00,1000.00,550000.00,18000.00,550.00,200.00,0.00,0.00,3226.22,2347.44,-0.3744
+1,550.00,200.00,5000.00,1000.00,19700.00,12000.00,13014.00,9467.00,10000.00,500000.00,550000.00,18000.00,124531.00,625731.00,501200.00,47181.00,10000.00,500000.00,1000.00,550000.00,18000.00,550.00,200.00,0.00,0.00,3226.22,2347.44,-0.3744
+0,550.00,200.00,5000.00,1000.00,19700.00,12000.00,13000.80,9467.00,10000.00,500000.00,550000.00,18000.00,124517.80,625717.80,501200.00,47167.80,10000.00,500000.00,1000.00,550000.00,18000.00,550.00,200.00,0.00,0.00,3226.22,2347.44,-0.3744
\ No newline at end of file
diff --git a/test/fixtures/transactions.yml b/test/fixtures/transactions.yml
index 410a4265..89576991 100644
--- a/test/fixtures/transactions.yml
+++ b/test/fixtures/transactions.yml
@@ -39,12 +39,46 @@ checking_five:
   currency: USD
   merchant: netflix
 
-# Savings account that has these transactions and valuation overrides
+checking_six_payment:
+  name: Payment to Credit Card
+  date: <%= 29.days.ago.to_date %>
+  amount: 100
+  account: checking
+  currency: USD
+  marked_as_transfer: true
+  transfer: credit_card_payment
+
+checking_seven_transfer:
+  name: Transfer to Savings
+  date: <%= 30.days.ago.to_date %>
+  amount: 250
+  account: checking
+  currency: USD
+  marked_as_transfer: true
+  transfer: savings_transfer
+
+checking_eight_external_payment:
+  name: Transfer TO external CC account (owned by user but not known to app)
+  date: <%= 30.days.ago.to_date %>
+  amount: 800
+  account: checking
+  currency: USD
+  marked_as_transfer: true
+
+checking_nine_external_transfer:
+  name: Transfer FROM external investing account (owned by user but not known to app)
+  date: <%= 30.days.ago.to_date %>
+  amount: -200
+  account: checking
+  currency: USD
+  marked_as_transfer: true
+
+# Savings account that has transactions and valuation overrides
 savings_one:
   name: Interest Received
   date: <%= 5.days.ago.to_date %>
   amount: -200
-  account: savings_with_valuation_overrides
+  account: savings
   category: income
   currency: USD
 
@@ -52,7 +86,7 @@ savings_two:
   name: Check Deposit
   date: <%= 12.days.ago.to_date %>
   amount: -50
-  account: savings_with_valuation_overrides
+  account: savings
   category: income
   currency: USD
 
@@ -60,17 +94,26 @@ savings_three:
   name: Withdrawal
   date: <%= 18.days.ago.to_date %>
   amount: 2000
-  account: savings_with_valuation_overrides
+  account: savings
   currency: USD
 
 savings_four:
   name: Check Deposit
   date: <%= 29.days.ago.to_date %>
   amount: -500
-  account: savings_with_valuation_overrides
+  account: savings
   category: income
   currency: USD
 
+savings_five_transfer:
+  name: Received Transfer from Checking Account
+  date: <%= 30.days.ago.to_date %>
+  amount: -250
+  account: savings
+  currency: USD
+  marked_as_transfer: true
+  transfer: savings_transfer
+
 # Credit card account transactions
 credit_card_one:
   name: Starbucks
@@ -96,12 +139,14 @@ credit_card_three:
   currency: USD
   merchant: amazon
 
-credit_card_four:
-  name: CC Payment
-  date: <%= 29.days.ago.to_date %>
+credit_card_four_payment:
+  name: Received CC Payment from Checking Account
+  date: <%= 30.days.ago.to_date %>
   amount: -100
   account: credit_card
   currency: USD
+  marked_as_transfer: true
+  transfer: credit_card_payment
 
 # eur_checking transactions
 eur_checking_one:
@@ -120,7 +165,7 @@ eur_checking_two:
 
 eur_checking_three:
   name: Check
-  date: <%= 29.days.ago.to_date %>
+  date: <%= 30.days.ago.to_date %>
   amount: -200
   currency: EUR
   account: eur_checking
@@ -143,7 +188,7 @@ multi_currency_two:
 multi_currency_three:
   name: Outflow 2
   date: <%= 19.days.ago.to_date %>
-  amount: 100
+  amount: 110.85
   currency: EUR
   account: multi_currency
 
diff --git a/test/fixtures/transfers.yml b/test/fixtures/transfers.yml
new file mode 100644
index 00000000..3c723a8e
--- /dev/null
+++ b/test/fixtures/transfers.yml
@@ -0,0 +1,2 @@
+credit_card_payment: { }
+savings_transfer: { }
diff --git a/test/fixtures/valuations.yml b/test/fixtures/valuations.yml
index eef16227..51bb3374 100644
--- a/test/fixtures/valuations.yml
+++ b/test/fixtures/valuations.yml
@@ -11,21 +11,45 @@ collectable_two:
 
 collectable_three:
   value: 400
-  date: <%= 30.days.ago.to_date %>
+  date: <%= 31.days.ago.to_date %>
   account: collectable
 
-# For checking account that has valuations and transactions
-savings_one:
-  value: 20500
-  date: <%= 3.days.ago.to_date %>
-  account: savings_with_valuation_overrides
+iou_one:
+  value: 200
+  date: <%= 31.days.ago.to_date %>
+  account: iou
 
-savings_two:
+multi_currency_one:
+  value: 10200
+  date: <%= 31.days.ago.to_date %>
+  account: multi_currency
+
+savings_one:
   value: 19500
   date: <%= 12.days.ago.to_date %>
-  account: savings_with_valuation_overrides
+  account: savings
 
-savings_three:
+savings_two:
   value: 21000
   date: <%= 25.days.ago.to_date %>
-  account: savings_with_valuation_overrides
+  account: savings
+
+brokerage_one:
+  value: 10000
+  date: <%= 31.days.ago.to_date %>
+  account: brokerage
+
+mortgage_loan_one:
+  value: 500000
+  date: <%= 31.days.ago.to_date %>
+  account: mortgage_loan
+
+house_one:
+  value: 550000
+  date: <%= 31.days.ago.to_date %>
+  account: house
+
+car_one:
+  value: 18000
+  date: <%= 31.days.ago.to_date %>
+  account: car
\ No newline at end of file
diff --git a/test/models/account/balance/calculator_test.rb b/test/models/account/balance/calculator_test.rb
index 05a9abaf..19ad1bf9 100644
--- a/test/models/account/balance/calculator_test.rb
+++ b/test/models/account/balance/calculator_test.rb
@@ -2,111 +2,82 @@ require "test_helper"
 require "csv"
 
 class Account::Balance::CalculatorTest < ActiveSupport::TestCase
-  # See: https://docs.google.com/spreadsheets/d/18LN5N-VLq4b49Mq1fNwF7_eBiHSQB46qQduRtdAEN98/edit?usp=sharing
-  setup do
-    @expected_balances = CSV.read("test/fixtures/account/expected_balances.csv", headers: true).map do |row|
-      {
-        "date" => (Date.current + row["date_offset"].to_i.days).to_date,
-        "collectable" => row["collectable"],
-        "checking" => row["checking"],
-        "savings_with_valuation_overrides" => row["savings_with_valuation_overrides"],
-        "credit_card" => row["credit_card"],
-        "multi_currency" => row["multi_currency"],
+  include FamilySnapshotTestHelper
 
-        # Balances should be calculated for all currencies of an account
-        "eur_checking_eur" => row["eur_checking_eur"],
-        "eur_checking_usd" => row["eur_checking_usd"]
-      }
+  test "syncs other asset balances" do
+    expected_balances = get_expected_balances_for(:collectable)
+    assert_account_balances calculated_balances_for(:collectable), expected_balances
+  end
+
+  test "syncs other liability balances" do
+    expected_balances = get_expected_balances_for(:iou)
+    assert_account_balances calculated_balances_for(:iou), expected_balances
+  end
+
+  test "syncs credit balances" do
+    expected_balances = get_expected_balances_for :credit_card
+    assert_account_balances calculated_balances_for(:credit_card), expected_balances
+  end
+
+  test "syncs checking account balances" do
+    expected_balances = get_expected_balances_for(:checking)
+    assert_account_balances calculated_balances_for(:checking), expected_balances
+  end
+
+  test "syncs foreign checking account balances" do
+    # Foreign accounts will generate balances for all currencies
+    expected_usd_balances = get_expected_balances_for(:eur_checking_usd)
+    expected_eur_balances = get_expected_balances_for(:eur_checking_eur)
+
+    calculated_balances = calculated_balances_for(:eur_checking)
+    calculated_usd_balances = calculated_balances.select { |b| b[:currency] == "USD" }
+    calculated_eur_balances = calculated_balances.select { |b| b[:currency] == "EUR" }
+
+    assert_account_balances calculated_usd_balances, expected_usd_balances
+    assert_account_balances calculated_eur_balances, expected_eur_balances
+  end
+
+  test "syncs multi-currency checking account balances" do
+    expected_balances = get_expected_balances_for(:multi_currency)
+    assert_account_balances calculated_balances_for(:multi_currency), expected_balances
+  end
+
+  test "syncs savings accounts balances" do
+    expected_balances = get_expected_balances_for(:savings)
+    assert_account_balances calculated_balances_for(:savings), expected_balances
+  end
+
+  test "syncs investment account balances" do
+    expected_balances = get_expected_balances_for(:brokerage)
+    assert_account_balances calculated_balances_for(:brokerage), expected_balances
+  end
+
+  test "syncs loan account balances" do
+    expected_balances = get_expected_balances_for(:mortgage_loan)
+    assert_account_balances calculated_balances_for(:mortgage_loan), expected_balances
+  end
+
+  test "syncs property account balances" do
+    expected_balances = get_expected_balances_for(:house)
+    assert_account_balances calculated_balances_for(:house), expected_balances
+  end
+
+  test "syncs vehicle account balances" do
+    expected_balances = get_expected_balances_for(:car)
+    assert_account_balances calculated_balances_for(:car), expected_balances
+  end
+
+  private
+    def assert_account_balances(actual_balances, expected_balances)
+      assert_equal expected_balances.count, actual_balances.count
+
+      actual_balances.each do |ab|
+        expected_balance = expected_balances.find { |eb| eb[:date] == ab[:date] }
+        assert_in_delta expected_balance[:balance], ab[:balance], 0.01, "Balance incorrect on date: #{ab[:date]}"
+      end
     end
-  end
 
-  test "syncs account with only valuations" do
-    account = accounts(:collectable)
-
-    calculator = Account::Balance::Calculator.new(account)
-    calculator.calculate
-
-    expected = @expected_balances.map { |row| row["collectable"].to_d }
-    actual = calculator.daily_balances.map { |b| b[:balance] }
-
-    assert_equal expected, actual
-  end
-
-  test "syncs account with only transactions" do
-    account = accounts(:checking)
-
-    calculator = Account::Balance::Calculator.new(account)
-    calculator.calculate
-
-    expected = @expected_balances.map { |row| row["checking"].to_d }
-    actual = calculator.daily_balances.map { |b| b[:balance] }
-
-    assert_equal expected, actual
-  end
-
-  test "syncs account with both valuations and transactions" do
-    account = accounts(:savings_with_valuation_overrides)
-
-    calculator = Account::Balance::Calculator.new(account)
-    calculator.calculate
-
-    expected = @expected_balances.map { |row| row["savings_with_valuation_overrides"].to_d }
-    actual = calculator.daily_balances.map { |b| b[:balance] }
-
-    assert_equal expected, actual
-  end
-
-  test "syncs liability account" do
-    account = accounts(:credit_card)
-
-    calculator = Account::Balance::Calculator.new(account)
-    calculator.calculate
-
-    expected = @expected_balances.map { |row| row["credit_card"].to_d }
-    actual = calculator.daily_balances.map { |b| b[:balance] }
-
-    assert_equal expected, actual
-  end
-
-  test "syncs foreign currency account" do
-    account = accounts(:eur_checking)
-    calculator = Account::Balance::Calculator.new(account)
-    calculator.calculate
-
-    # Calculator should calculate balances in both account and family currency
-    expected_eur_balances = @expected_balances.map { |row| row["eur_checking_eur"].to_d }
-    expected_usd_balances = @expected_balances.map { |row| row["eur_checking_usd"].to_d }
-
-    actual_eur_balances = calculator.daily_balances.select { |b| b[:currency] == "EUR" }.sort_by { |b| b[:date] }.map { |b| b[:balance] }
-    actual_usd_balances = calculator.daily_balances.select { |b| b[:currency] == "USD" }.sort_by { |b| b[:date] }.map { |b| b[:balance] }
-
-    assert_equal expected_eur_balances, actual_eur_balances
-    assert_equal expected_usd_balances, actual_usd_balances
-  end
-
-  test "syncs multi currency account" do
-    account = accounts(:multi_currency)
-    calculator = Account::Balance::Calculator.new(account)
-    calculator.calculate
-
-    expected_balances = @expected_balances.map { |row| row["multi_currency"].to_d }
-
-    actual_balances = calculator.daily_balances.map { |b| b[:balance] }
-
-    assert_equal expected_balances, actual_balances
-  end
-
-  test "syncs with overridden start date" do
-    account = accounts(:multi_currency)
-    account.sync
-    calc_start_date = 10.days.ago.to_date
-    calculator = Account::Balance::Calculator.new(account, { calc_start_date: })
-    calculator.calculate
-
-    expected_balances = @expected_balances.filter { |row| row["date"] >= calc_start_date }.map { |row| row["multi_currency"].to_d }
-
-    actual_balances = calculator.daily_balances.map { |b| b[:balance] }
-
-    assert_equal expected_balances, actual_balances
-  end
+    def calculated_balances_for(account_key)
+      Account::Balance::Calculator.new(accounts(account_key)).calculate.daily_balances
+    end
 end
diff --git a/test/models/account/syncable_test.rb b/test/models/account/syncable_test.rb
index cb9d2655..e6afdf5f 100644
--- a/test/models/account/syncable_test.rb
+++ b/test/models/account/syncable_test.rb
@@ -4,7 +4,7 @@ class Account::SyncableTest < ActiveSupport::TestCase
   include ActiveJob::TestHelper
 
   setup do
-    @account = accounts(:savings_with_valuation_overrides)
+    @account = accounts(:savings)
   end
 
   test "triggers sync job" do
@@ -14,27 +14,27 @@ class Account::SyncableTest < ActiveSupport::TestCase
   end
 
   test "account has no balances until synced" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
 
     assert_equal 0, account.balances.count
   end
 
   test "account has balances after syncing" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
     account.sync
 
-    assert_equal 31, account.balances.count
+    assert_equal 32, account.balances.count
   end
 
   test "partial sync with missing historical balances performs a full sync" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
     account.sync 10.days.ago.to_date
 
-    assert_equal 31, account.balances.count
+    assert_equal 32, account.balances.count
   end
 
   test "balances are updated after syncing" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
     balance_date = 10.days.ago
     account.balances.create!(date: balance_date, balance: 1000)
     account.sync
@@ -43,7 +43,7 @@ class Account::SyncableTest < ActiveSupport::TestCase
   end
 
   test "balances before sync start date are not updated after syncing" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
     balance_date = 10.days.ago
     account.balances.create!(date: balance_date, balance: 1000)
     account.sync 5.days.ago.to_date
@@ -52,7 +52,7 @@ class Account::SyncableTest < ActiveSupport::TestCase
   end
 
   test "balances after sync start date are updated after syncing" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
     balance_date = 10.days.ago
     account.balances.create!(date: balance_date, balance: 1000)
     account.sync 20.days.ago.to_date
@@ -61,7 +61,7 @@ class Account::SyncableTest < ActiveSupport::TestCase
   end
 
   test "balance on the sync date is updated after syncing" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
     balance_date = 5.days.ago
     account.balances.create!(date: balance_date, balance: 1000)
     account.sync balance_date.to_date
@@ -73,13 +73,13 @@ class Account::SyncableTest < ActiveSupport::TestCase
     account = accounts(:eur_checking)
     account.sync
 
-    assert_equal 62, account.balances.count
-    assert_equal 31, account.balances.where(currency: "EUR").count
-    assert_equal 31, account.balances.where(currency: "USD").count
+    assert_equal 64, account.balances.count
+    assert_equal 32, account.balances.where(currency: "EUR").count
+    assert_equal 32, account.balances.where(currency: "USD").count
   end
 
   test "stale balances are purged after syncing" do
-    account = accounts(:savings_with_valuation_overrides)
+    account = accounts(:savings)
 
     # Create old, stale balances that should be purged (since they are before account start date)
     account.balances.create!(date: 1.year.ago, balance: 1000)
@@ -88,14 +88,6 @@ class Account::SyncableTest < ActiveSupport::TestCase
 
     account.sync
 
-    assert_equal 31, account.balances.count
-  end
-
-  test "account balance is updated after sync" do
-    account = accounts(:savings_with_valuation_overrides)
-
-    assert_changes -> { account.balance }, to: 20500 do
-      account.sync
-    end
+    assert_equal 32, account.balances.count
   end
 end
diff --git a/test/models/account_test.rb b/test/models/account_test.rb
index 949335c6..f0894354 100644
--- a/test/models/account_test.rb
+++ b/test/models/account_test.rb
@@ -5,16 +5,6 @@ class AccountTest < ActiveSupport::TestCase
   def setup
     @account = accounts(:checking)
     @family = families(:dylan_family)
-    @snapshots = CSV.read("test/fixtures/family/expected_snapshots.csv", headers: true).map do |row|
-      {
-        "date" => (Date.current + row["date_offset"].to_i.days).to_date,
-        "assets" => row["assets"],
-        "liabilities" => row["liabilities"],
-        "Account::Depository" => row["depositories"],
-        "Account::Credit" => row["credits"],
-        "Account::OtherAsset" => row["other_assets"]
-      }
-    end
   end
 
   test "new account should be valid" do
@@ -47,26 +37,23 @@ class AccountTest < ActiveSupport::TestCase
   test "syncs regular account" do
     @account.sync
     assert_equal "ok", @account.status
-    assert_equal 31, @account.balances.count
+    assert_equal 32, @account.balances.count
   end
 
   test "syncs foreign currency account" do
     account = accounts(:eur_checking)
     account.sync
     assert_equal "ok", account.status
-    assert_equal 31, account.balances.where(currency: "USD").count
-    assert_equal 31, account.balances.where(currency: "EUR").count
+    assert_equal 32, account.balances.where(currency: "USD").count
+    assert_equal 32, account.balances.where(currency: "EUR").count
   end
+
   test "groups accounts by type" do
     @family.accounts.each do |account|
       account.sync
     end
 
     result = @family.accounts.by_group(period: Period.all)
-
-    expected_assets = @snapshots.last["assets"].to_d
-    expected_liabilities = @snapshots.last["liabilities"].to_d
-
     assets = result[:assets]
     liabilities = result[:liabilities]
 
@@ -84,14 +71,14 @@ class AccountTest < ActiveSupport::TestCase
     other_liabilities = liabilities.children.find { |group| group.name == "Account::OtherLiability" }
 
     assert_equal 4, depositories.children.count
-    assert_equal 0, properties.children.count
-    assert_equal 0, vehicles.children.count
-    assert_equal 0, investments.children.count
+    assert_equal 1, properties.children.count
+    assert_equal 1, vehicles.children.count
+    assert_equal 1, investments.children.count
     assert_equal 1, other_assets.children.count
 
     assert_equal 1, credits.children.count
-    assert_equal 0, loans.children.count
-    assert_equal 0, other_liabilities.children.count
+    assert_equal 1, loans.children.count
+    assert_equal 1, other_liabilities.children.count
   end
 
   test "generates series with last balance equal to current account balance" do
diff --git a/test/models/family_test.rb b/test/models/family_test.rb
index ba57279b..fc9ff284 100644
--- a/test/models/family_test.rb
+++ b/test/models/family_test.rb
@@ -2,26 +2,13 @@ require "test_helper"
 require "csv"
 
 class FamilyTest < ActiveSupport::TestCase
+  include FamilySnapshotTestHelper
+
   def setup
     @family = families(:dylan_family)
-
     @family.accounts.each do |account|
       account.sync
     end
-
-    # See this Google Sheet for calculations and expected results for dylan_family:
-    # https://docs.google.com/spreadsheets/d/18LN5N-VLq4b49Mq1fNwF7_eBiHSQB46qQduRtdAEN98/edit?usp=sharing
-    @expected_snapshots = CSV.read("test/fixtures/family/expected_snapshots.csv", headers: true).map do |row|
-      {
-        "date" => (Date.current + row["date_offset"].to_i.days).to_date,
-        "net_worth" => row["net_worth"],
-        "assets" => row["assets"],
-        "liabilities" => row["liabilities"],
-        "rolling_spend" => row["rolling_spend"],
-        "rolling_income" => row["rolling_income"],
-        "savings_rate" => row["savings_rate"]
-      }
-    end
   end
 
   test "should have many users" do
@@ -58,57 +45,62 @@ class FamilyTest < ActiveSupport::TestCase
   end
 
   test "should calculate total assets" do
-    expected = @expected_snapshots.last["assets"].to_d
-    assert_equal Money.new(expected), @family.assets
+    expected = get_today_snapshot_value_for :assets
+    assert_in_delta expected, @family.assets.amount, 0.01
   end
 
   test "should calculate total liabilities" do
-    expected = @expected_snapshots.last["liabilities"].to_d
-    assert_equal Money.new(expected), @family.liabilities
+    expected = get_today_snapshot_value_for :liabilities
+    assert_in_delta expected, @family.liabilities.amount, 0.01
   end
 
   test "should calculate net worth" do
-    expected = @expected_snapshots.last["net_worth"].to_d
-    assert_equal Money.new(expected), @family.net_worth
+    expected = get_today_snapshot_value_for :net_worth
+    assert_in_delta expected, @family.net_worth.amount, 0.01
   end
 
-  test "should calculate snapshot correctly" do
-    asset_series = @family.snapshot[:asset_series]
-    liability_series = @family.snapshot[:liability_series]
-    net_worth_series = @family.snapshot[:net_worth_series]
+  test "calculates asset time series" do
+    series = @family.snapshot[:asset_series]
+    expected_series = get_expected_balances_for :assets
 
-    assert_equal @expected_snapshots.count, asset_series.values.count
-    assert_equal @expected_snapshots.count, liability_series.values.count
-    assert_equal @expected_snapshots.count, net_worth_series.values.count
-
-    @expected_snapshots.each_with_index do |row, index|
-      expected_assets = TimeSeries::Value.new(date: row["date"], value: Money.new(row["assets"].to_d))
-      expected_liabilities = TimeSeries::Value.new(date: row["date"], value: Money.new(row["liabilities"].to_d))
-      expected_net_worth = TimeSeries::Value.new(date: row["date"], value: Money.new(row["net_worth"].to_d))
-
-      assert_in_delta expected_assets.value.amount, Money.new(asset_series.values[index].value).amount, 0.01
-      assert_in_delta expected_liabilities.value.amount, Money.new(liability_series.values[index].value).amount, 0.01
-      assert_in_delta expected_net_worth.value.amount, Money.new(net_worth_series.values[index].value).amount, 0.01
-    end
+    assert_time_series_balances series, expected_series
   end
 
-  test "should calculate transaction snapshot correctly" do
-    spending_series = @family.snapshot_transactions[:spending_series]
-    income_series = @family.snapshot_transactions[:income_series]
-    savings_rate_series = @family.snapshot_transactions[:savings_rate_series]
+  test "calculates liability time series" do
+    series = @family.snapshot[:liability_series]
+    expected_series = get_expected_balances_for :liabilities
 
-    assert_equal @expected_snapshots.count, spending_series.values.count
-    assert_equal @expected_snapshots.count, income_series.values.count
-    assert_equal @expected_snapshots.count, savings_rate_series.values.count
+    assert_time_series_balances series, expected_series
+  end
 
-    @expected_snapshots.each_with_index do |row, index|
-      expected_spending = TimeSeries::Value.new(date: row["date"], value: Money.new(row["rolling_spend"].to_d))
-      expected_income = TimeSeries::Value.new(date: row["date"], value: Money.new(row["rolling_income"].to_d))
-      expected_savings_rate = TimeSeries::Value.new(date: row["date"], value: Money.new(row["savings_rate"].to_d))
+  test "calculates net worth time series" do
+    series = @family.snapshot[:net_worth_series]
+    expected_series = get_expected_balances_for :net_worth
 
-      assert_in_delta expected_spending.value.amount, Money.new(spending_series.values[index].value).amount, 0.01
-      assert_in_delta expected_income.value.amount, Money.new(income_series.values[index].value).amount, 0.01
-      assert_in_delta expected_savings_rate.value.amount, savings_rate_series.values[index].value, 0.01
+    assert_time_series_balances series, expected_series
+  end
+
+  test "calculates rolling expenses" do
+    series = @family.snapshot_transactions[:spending_series]
+    expected_series = get_expected_balances_for :rolling_spend
+
+    assert_time_series_balances series, expected_series, ignore_count: true
+  end
+
+  test "calculates rolling income" do
+    series = @family.snapshot_transactions[:income_series]
+    expected_series = get_expected_balances_for :rolling_income
+
+    assert_time_series_balances series, expected_series, ignore_count: true
+  end
+
+  test "calculates savings rate series" do
+    series = @family.snapshot_transactions[:savings_rate_series]
+    expected_series = get_expected_balances_for :savings_rate
+
+    series.values.each do |tsb|
+      expected_balance = expected_series.find { |eb| eb[:date] == tsb.date }
+      assert_in_delta expected_balance[:balance], tsb.value, 0.0001, "Balance incorrect on date: #{tsb.date}"
     end
   end
 
@@ -127,4 +119,15 @@ class FamilyTest < ActiveSupport::TestCase
     assert_equal liabilities_before - disabled_cc.balance, @family.liabilities
     assert_equal net_worth_before - disabled_checking.balance + disabled_cc.balance, @family.net_worth
   end
+
+  private
+
+    def assert_time_series_balances(time_series_balances, expected_balances, ignore_count: false)
+      assert_equal time_series_balances.values.count, expected_balances.count unless ignore_count
+
+      time_series_balances.values.each do |tsb|
+        expected_balance = expected_balances.find { |eb| eb[:date] == tsb.date }
+        assert_in_delta expected_balance[:balance], tsb.value.amount, 0.01, "Balance incorrect on date: #{tsb.date}"
+      end
+    end
 end
diff --git a/test/models/transaction_test.rb b/test/models/transaction_test.rb
index 5e21f065..141b294c 100644
--- a/test/models/transaction_test.rb
+++ b/test/models/transaction_test.rb
@@ -3,6 +3,7 @@ require "test_helper"
 class TransactionTest < ActiveSupport::TestCase
   setup do
     @transaction = transactions(:checking_one)
+    @family = families(:dylan_family)
   end
 
   # See: https://github.com/maybe-finance/maybe/wiki/vision#signage-of-money
@@ -41,4 +42,14 @@ class TransactionTest < ActiveSupport::TestCase
     current_transaction.account.expects(:sync_later).with(prior_transaction.date)
     current_transaction.sync_account_later
   end
+
+  test "can calculate total spending for a group of transactions" do
+    assert_equal Money.new(2135), @family.transactions.expense_total("USD")
+    assert_equal Money.new(1010.85, "EUR"), @family.transactions.expense_total("EUR")
+  end
+
+  test "can calculate total income for a group of transactions" do
+    assert_equal -Money.new(2075), @family.transactions.income_total("USD")
+    assert_equal -Money.new(250, "EUR"), @family.transactions.income_total("EUR")
+  end
 end
diff --git a/test/models/transfer_test.rb b/test/models/transfer_test.rb
new file mode 100644
index 00000000..2d1b26cd
--- /dev/null
+++ b/test/models/transfer_test.rb
@@ -0,0 +1,49 @@
+require "test_helper"
+
+class TransferTest < ActiveSupport::TestCase
+  setup do
+    # Transfers can be posted on different dates
+    @outflow = accounts(:checking).transactions.create! date: 1.day.ago.to_date, name: "Transfer to Savings", amount: 100, marked_as_transfer: true
+    @inflow = accounts(:savings).transactions.create! date: Date.current, name: "Transfer from Savings", amount: -100, marked_as_transfer: true
+  end
+
+  test "transfer valid if it has inflow and outflow from different accounts for the same amount" do
+    transfer = Transfer.create! transactions: [ @inflow, @outflow ]
+
+    assert transfer.valid?
+  end
+
+  test "transfer must have 2 transactions" do
+    invalid_transfer_1 = Transfer.new transactions: [ @outflow ]
+    invalid_transfer_2 = Transfer.new transactions: [ @inflow, @outflow, transactions(:savings_four) ]
+
+    assert invalid_transfer_1.invalid?
+    assert invalid_transfer_2.invalid?
+  end
+
+  test "transfer cannot have 2 transactions from the same account" do
+    account = accounts(:checking)
+    inflow = account.transactions.create! date: Date.current, name: "Inflow", amount: -100
+    outflow = account.transactions.create! date: Date.current, name: "Outflow", amount: 100
+
+    assert_raise ActiveRecord::RecordInvalid do
+      Transfer.create! transactions: [ inflow, outflow ]
+    end
+  end
+
+  test "all transfer transactions must be marked as transfers" do
+    @inflow.update! marked_as_transfer: false
+
+    assert_raise ActiveRecord::RecordInvalid do
+      Transfer.create! transactions: [ @inflow, @outflow ]
+    end
+  end
+
+  test "transfer transactions must net to zero" do
+    @outflow.update! amount: 105
+
+    assert_raises ActiveRecord::RecordInvalid do
+      Transfer.create! transactions: [ @inflow, @outflow ]
+    end
+  end
+end
diff --git a/test/models/value_group_test.rb b/test/models/value_group_test.rb
index c571e78d..3b0c676d 100644
--- a/test/models/value_group_test.rb
+++ b/test/models/value_group_test.rb
@@ -3,7 +3,7 @@ require "ostruct"
 class ValueGroupTest < ActiveSupport::TestCase
     setup do
         checking = accounts(:checking)
-        savings = accounts(:savings_with_valuation_overrides)
+        savings = accounts(:savings)
         collectable = accounts(:collectable)
 
         # Level 1
diff --git a/test/support/family_snapshot_test_helper.rb b/test/support/family_snapshot_test_helper.rb
new file mode 100644
index 00000000..f691f34f
--- /dev/null
+++ b/test/support/family_snapshot_test_helper.rb
@@ -0,0 +1,21 @@
+module FamilySnapshotTestHelper
+  # See: https://docs.google.com/spreadsheets/d/18LN5N-VLq4b49Mq1fNwF7_eBiHSQB46qQduRtdAEN98/edit?usp=sharing
+  def get_expected_balances_for(key)
+    expected_results_file.map do |row|
+      {
+        date: (Date.current - row["date_offset"].to_i.days).to_date,
+        balance: row[key.to_s].to_d
+      }
+    end
+  end
+
+  def get_today_snapshot_value_for(metric)
+    expected_results_file[-1][metric.to_s].to_d
+  end
+
+  private
+
+    def expected_results_file
+      CSV.read("test/fixtures/files/expected_family_snapshots.csv", headers: true)
+    end
+end
diff --git a/test/system/transactions_test.rb b/test/system/transactions_test.rb
index fa3d8c89..3dd2d585 100644
--- a/test/system/transactions_test.rb
+++ b/test/system/transactions_test.rb
@@ -134,7 +134,7 @@ class TransactionsTest < ApplicationSystemTestCase
     def number_of_transactions_on_page
       page_size = 50
 
-      [ @user.family.transactions.count, page_size ].min
+      [ @user.family.transactions.where(transfer_id: nil).count, page_size ].min
     end
 
     def all_transactions_checkbox