diff --git a/app/controllers/bookingsync_portal/admin/rentals_controller.rb b/app/controllers/bookingsync_portal/admin/rentals_controller.rb
index 665f8349..751fa911 100644
--- a/app/controllers/bookingsync_portal/admin/rentals_controller.rb
+++ b/app/controllers/bookingsync_portal/admin/rentals_controller.rb
@@ -5,19 +5,44 @@ class RentalsController < Admin::BaseController
       before_action :fetch_remote_rentals, only: :index
 
       def index
-        @not_connected_rentals = current_account.rentals.visible.ordered.not_connected
-        @visible_rentals = current_account.rentals.visible
-        @remote_accounts = current_account.remote_accounts
-        @remote_rentals_by_account = current_account.remote_rentals.ordered
-          .includes(:remote_account, :rental).group_by(&:remote_account)
+        render :index, locals: { **index_arguments }
       end
 
       def show
         rental
       end
 
+      def index_arguments
+        BookingsyncPortal.custom_arguments.dig("Admin", "RentalsController", "index") || {
+          not_connected_rentals: not_connected_rentals.call(current_account),
+          visible_rentals: visible_rentals.call(current_account),
+          remote_accounts: remote_accounts.call(current_account),
+          remote_rentals_by_account: remote_rentals_by_account.call(current_account)
+        }
+      end
+
       private
 
+      def not_connected_rentals
+        BookingsyncPortal.not_connected_rentals || lambda {
+          |account| account.rentals.visible.ordered.not_connected
+        }
+      end
+      
+      def visible_rentals
+        BookingsyncPortal.visible_rentals || lambda { |account| account.rentals.visible }
+      end
+      
+      def remote_accounts
+        BookingsyncPortal.remote_accounts ||  lambda { |account| account.remote_accounts }
+      end
+      
+      def remote_rentals_by_account
+        BookingsyncPortal.remote_rentals_by_account || lambda {
+          |account| account.remote_rentals.ordered.includes(:remote_account, :rental).group_by(&:remote_account)
+        }
+      end
+
       def synchronize_rentals
         BookingsyncPortal.rental_model.constantize.synchronize(scope: current_account)
       end
diff --git a/app/views/bookingsync_portal/admin/rentals/index.html.erb b/app/views/bookingsync_portal/admin/rentals/index.html.erb
index ff40aadb..9c818e59 100644
--- a/app/views/bookingsync_portal/admin/rentals/index.html.erb
+++ b/app/views/bookingsync_portal/admin/rentals/index.html.erb
@@ -10,8 +10,8 @@
         <legend class="text-center"><%= image_tag('bookingsync_portal/bookingsync.png', alt: 'BookingSync') %></legend>
       </div>
       <div class="rentals-list-scroll">
-        <%= render "rentals", visible_rentals: @visible_rentals,
-          not_connected_rentals: @not_connected_rentals %>
+        <%= render "rentals", visible_rentals: visible_rentals,
+          not_connected_rentals: not_connected_rentals %>
       </div>
     </div>
   </div>
@@ -26,11 +26,11 @@
       </div>
 
       <div class="rentals-list-scroll">
-        <% @remote_accounts.each do |remote_account| %>
+        <% remote_accounts.each do |remote_account| %>
           <h3><%=t '.remote_header', portal_name: BookingsyncPortal.portal_name,
             account_name: remote_account.name %></h3>
-          <%- if Array(@remote_rentals_by_account[remote_account]).length > 0 -%>
-            <% Array(@remote_rentals_by_account[remote_account]).each do |remote_rental| %>
+          <%- if Array(remote_rentals_by_account[remote_account]).length > 0 -%>
+            <% Array(remote_rentals_by_account[remote_account]).each do |remote_rental| %>
               <% if remote_rental.connected? %>
                 <%= render "connected_rental", remote_rental: remote_rental, rental: remote_rental.rental %>
               <% else %>
diff --git a/lib/bookingsync_portal.rb b/lib/bookingsync_portal.rb
index e5b124f6..d0295ee7 100644
--- a/lib/bookingsync_portal.rb
+++ b/lib/bookingsync_portal.rb
@@ -60,6 +60,14 @@ module BookingsyncPortal
   # message bus channel scope
   mattr_accessor :message_bus_channel_scope
 
+  mattr_accessor :not_connected_rentals
+  mattr_accessor :visible_rentals
+  mattr_accessor :remote_accounts
+  mattr_accessor :remote_rentals_by_account
+
+  mattr_accessor :custom_arguments
+  @@custom_arguments = {}
+
   # fetch remote rentals
   def self.fetch_remote_rentals(account)
     # return false if remote account is not present or not valid
diff --git a/spec/controllers/admin/rentals_controller_spec.rb b/spec/controllers/admin/rentals_controller_spec.rb
index 30cc3d70..14c37b80 100644
--- a/spec/controllers/admin/rentals_controller_spec.rb
+++ b/spec/controllers/admin/rentals_controller_spec.rb
@@ -1,7 +1,6 @@
-require 'rails_helper'
+require "rails_helper"
 
 describe BookingsyncPortal::Admin::RentalsController do
-  render_views
   routes { BookingsyncPortal::Engine.routes }
 
   let!(:account) { create(:account) }
@@ -11,11 +10,11 @@
   let!(:connection) { create(:connection, rental: rental_connected) }
 
   before do
-    request.env['HTTPS'] = 'on'
+    request.env["HTTPS"] = "on"
     allow(controller).to receive(:current_account).and_return(account)
   end
 
-  describe 'GET #index' do
+  describe "GET #index" do
     before do
       expect(Rental).to receive(:synchronize).with(scope: account) do
         # pretending to sync rentals :P
@@ -23,8 +22,56 @@
       end
     end
 
-    it 'synchronizes rentals' do
-      expect { get :index }.to change { Rental.count }
+    context "methods from default config" do
+      render_views
+
+      it "synchronizes rentals" do
+        expect { get :index }.to change { Rental.count }
+      end
+    end
+    
+    context "using custom methods" do
+      let(:fake_connected_rental) { create(:rental, account: account) }
+      let(:fake_visible_rental) { create(:rental, account: account) }
+      let(:fake_remote_account) { create(:remote_account, account: account) }
+      let(:fake_remote_rental) { create(:remote_rental, account: account) }
+
+      let(:fake_connected_rentals_value) { [fake_connected_rental] }
+      let(:fake_visible_rental_value) { [fake_visible_rental] }
+      let(:fake_remote_accounts_value) { [fake_remote_account] }
+      let(:fake_remote_rentals_by_account_value) do
+        RemoteRental.where(id: fake_remote_rental).includes(:remote_account, :rental).group_by(&:remote_account)
+      end
+
+      before do
+        BookingsyncPortal.setup do |config|
+          config.not_connected_rentals = lambda { |account| fake_connected_rentals_value }
+          config.visible_rentals = lambda { |account| fake_visible_rental_value }
+          config.remote_accounts = lambda { |account| fake_remote_accounts_value }
+          config.remote_rentals_by_account = lambda { |account| fake_remote_rentals_by_account_value }
+        end
+        
+        allow(controller).to receive(:render)
+        allow(controller).to receive(:render).with(:index, an_instance_of(Hash))
+      end
+
+      it "calls custom methods" do
+        get :index
+
+        expect(BookingsyncPortal.not_connected_rentals.call(account)).to eq(fake_connected_rentals_value)
+        expect(BookingsyncPortal.visible_rentals.call(account)).to eq(fake_visible_rental_value)
+        expect(BookingsyncPortal.remote_accounts.call(account)).to eq(fake_remote_accounts_value)
+        expect(BookingsyncPortal.remote_rentals_by_account.call(account)).to eq(fake_remote_rentals_by_account_value)
+
+        expect(controller).to have_received(:render).at_least(1).times do |method, options|
+          if method == :index
+            expect(options.dig(:locals, :not_connected_rentals)).to eq(fake_connected_rentals_value)
+            expect(options.dig(:locals, :visible_rentals)).to eq(fake_visible_rental_value)
+            expect(options.dig(:locals, :remote_accounts)).to eq(fake_remote_accounts_value)
+            expect(options.dig(:locals, :remote_rentals_by_account)).to eq(fake_remote_rentals_by_account_value)
+          end
+        end
+      end
     end
   end
 end