Create Paypal Script

I am looking for a custom paypal script. I am not looking for some hack script from the internet. paypal script must be secure, and user must not be able to unlock/download the e-product until it is paid for. here is a description. I will do custom coding and I'm not going to send you a modified clone or anything similar. The script will have passkey for every file, a passkey for the file and is sent to the e-mail address of the buyer, the buyer will be able to download the file for x hours (you will be able to configure this), after this period the passkey will expire. If you want I will add another security measure, the bought file can be downloaded only by using the buyer's IP. If you have other ideas just let me know but I believe even these two are enough secure. Also, the script will be easy to use. You upload the file to a secure directory on the server and and the script will protect the directory, the [login to view URL] file will be located elsewhere and the IPN will send a file to the PayPal address of the buyer with the downloadlink. (it will send a link to [login to view URL] with passkey) The script also must allow multiple purchase options, and the script will send the buyer the key for the purchased items. if a buyer buys one product, then they will get a key for that one product, if they buy 3 products, then the buyer will get keys for the 3 products they bought. So I must be able to setup multiple eproducts and descriptions. The script will run as a page, so it must be attractive and professional design. for example, here is a simple nice looking design. The paypal page must look good, and not some text and thats it. <[login to view URL]> buyers have to trust who they are buying from, so if it is crappy design, do you think they are going to buy? Thanks for looking. ## Deliverables 1) All deliverables will be considered "work made for hire" under U.S. Copyright law. Employer will receive exclusive and complete copyrights to all work purchased. (No 3rd party components unless all copyright ramifications are explained AND AGREED TO by the employer on the site per the worker's Worker Legal Agreement). ## Platform php