Create Bump Sale using Lightbox type feature

Hi We need someone with experience with APIs (our payment gateway), PHP, AJAX and Javascript to create us a bump sale feature on our order page. This is how the workflow should go: 1. user come to our 1 page order form 2. they hit submit to process their order 3. when they hit submit a lightbox comes up asking them if they would like to add this offer to their order. 4. If they hit yes then it adds the amount of the bump sale to the total. 5. If they hit no, it offers them a downsale which is a another product for a lower price. 6. if they close out the lightbox it still takes their order for the orginal amount so we dont lose the sale. Our payment gateway is usaepay which is fully documented and we already have a sandbox account Some kind of email should be sent to an address to let us know that the bump has been bought or a field added to our order form in backend. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows? (depending on the nature? of the deliverables): a)? For web sites or? other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software? installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform IE, Firefox, Safari, Opera