Add deposits controller

app/models/deposit.rb

@@ -0,0 +1,23 @@
+class Deposit
+  include ActiveModel::Validations
+  include ActiveModel::Conversion
+  extend ActiveModel::Naming
+
+  attr_accessor :amount, :description, :registrar
+
+  validates :amount, :registrar, presence: true
+
+  def initialize(attributes = {})
+    attributes.each do |name, value|
+      send("#{name}=", value)
+    end
+  end
+
+  def persisted?
+    false
+  end
+
+  def issue_prepayment_invoice
+    valid? && registrar.issue_prepayment_invoice(amount, description)
+  end
+end