GetPaid (Formerly the Invoicing plugin) is a lightweight Payments and Invoicing system for WordPress. It can be used to sell anything online via payment forms or buy now buttons that can be added to any landing page. It can also be used by freelancers to manage their Invoices or by 3rd party Themes and Plugins as their payment system. GeoDirectory currently uses GetPaid as its payment system
Get the shortcode, like [getpaid item=14 button='Buy Now']
Place that on a new page. Dashboard -> Pages -> Add New.
View that page, and the total is not calculated when we click "Buy Now" on the form, and when we click "continue" it gives an error message. (The error message is "Please provide at least one item or amount." )