Upgrade membrship mode option for dating site

Hello freelancers, I am looking for a web programmer to make a upgrade membership option mode for users on dating site based on VLD personals CMS. There is already an upgrade mode for various payment gateways, but this option would allow users to upgrade their accounts by liking us on facebook. Here is description for it: The offer would be for users to "like" our facebook page and gain 7 days upgraded membership every month. So if month is 30days, they have 7 days upgraded and for the rest 23 they will have to upgrade by purchasing membership (or not), up to them. But when those 23 days end they will have again 7days free. However, it will need to have some protection system against fraud. Such as if they "like" us they gain upgraded membership, some of them will probably "unlike" so every time users logs in, it will need to check if users is still "liking" us, if they liked us in first place. If they don't that upgraded membership through facebook would be taken away from them. And of course they can "like" us again to gain it back, but if they used it for one day they will need to have only 6 days left not to reset to 7 again. So in some way I assume that facebook account would need to bound to theirs on site account. Let me know if you have any questions.