Custom credit-card processing addon for whmcs online system

We are looking to develop a custom module in PHP for WHMCS ([login to view URL]) processing online credit card payments via a proprietary processing gateway. The scope of the project is very small and specifications are clear. ## Deliverables Two pages need to be created that would be integrated with online billing system. No design is required, just basic HTML for the required functionality. 1. payment page with html form with required parameters (seller ID, amount to pay, etc) by submitting the form buyer is directed to the payment gateway 2. payment status page, displayed when the payment is processed, successfully or not