use log#sales?

app/helpers/tasklist_helper.rb

@@ -39,7 +39,7 @@ module TasklistHelper
 
   def review_log_text(log)
     if log.collection_period_open?
-      link = log.is_a?(SalesLog) ? review_sales_log_path(id: log, sales_log: true) : review_lettings_log_path(log)
+      link = log.sales? ? review_sales_log_path(id: log, sales_log: true) : review_lettings_log_path(log)
 
       "You can #{govuk_link_to 'review and make changes to this log', link} until #{log.form.end_date.to_formatted_s(:govuk_date)}.".html_safe
     else

app/models/lettings_log.rb

@@ -481,10 +481,6 @@ class LettingsLog < Log
     location.type_of_unit_before_type_cast if location
   end
 
-  def lettings?
-    true
-  end
-
   def rent_type_detail
     form.get_question("rent_type", self)&.label_from_value(rent_type)
   end

app/models/log.rb

@@ -40,7 +40,11 @@ class Log < ApplicationRecord
   end
 
   def lettings?
-    false
+    is_a? LettingsLog
+  end
+
+  def sales?
+    is_a? SalesLog
   end
 
   def ethnic_refused?

app/views/form/review.html.erb

@@ -1,4 +1,4 @@
-<% if @log.is_a? SalesLog %>
+<% if @log.sales? %>
   <% content_for :title, "Review sales log" %>
   <% content_for :breadcrumbs, govuk_breadcrumbs(breadcrumbs: {
     "Logs" => "/logs",

spec/models/lettings_log_spec.rb

@@ -18,6 +18,11 @@ RSpec.describe LettingsLog do
     expect(described_class).to be < ApplicationRecord
   end
 
+  it "is a not a sales log" do
+    lettings_log = FactoryBot.build(:lettings_log, created_by: created_by_user)
+    expect(lettings_log.sales?).to be false
+  end
+
   it "is a lettings log" do
     lettings_log = FactoryBot.build(:lettings_log, created_by: created_by_user)
     expect(lettings_log).to be_lettings

spec/models/sales_log_spec.rb

@@ -12,11 +12,16 @@ RSpec.describe SalesLog, type: :model do
     expect(described_class).to be < ApplicationRecord
   end
 
-  it "is a sales log" do
+  it "is a not a lettings log" do
     sales_log = build(:sales_log, created_by: created_by_user)
     expect(sales_log.lettings?).to be false
   end
 
+  it "is a sales log" do
+    sales_log = build(:sales_log, created_by: created_by_user)
+    expect(sales_log.sales?).to be true
+  end
+
   describe "#new" do
     context "when creating a record" do
       let(:sales_log) do