574197 WHMCS mod addon

I need a mod or addon programmed in whmcs. I want to send a direct link to someone that, when they login with an existing username (or register for one) they will be automatically credited X amount to their account that they can use to purchase existing products/services. Almost like a coupon, but they wouldn't need to buy anything at the time of purchase. I need it to have: 1. direct link to the crediting page 2. ability to adjust credit amount 3. ability to expire the link by day, number of times used, or infinte 4. ability to restrict credit use to once per account 5. ability to see how many people used the credit link 6. ability to see who used the credit link (either by a database add to their account pulled up by report or a single report with all users of that link, whatever is easier) 7. anything else that might be of importance to this.