We need to perform following tasks for the items in the cart
1) We need the clients to sign up for our services through a single page rather multiple page. We have an example to show you. So choosing products, capturing information and running our module should be done in one page. We use a module to create a specific product (not domain or hosting) so your single page should be able to run our module.
2) We have already set up a free trial add-on but we want to make sure it works fine so you should be able to test it and debug it if needed.
You should have good WHMCS skills; All communications will be in English; You should have reliable internet access.