Build a website

We would like to have a professional website builder to study this website [login to view URL] and produce something similar with a few changes so as not to be a direct duplicate. You must be experienced as we won't accept anything less. This is a system that will automatically pair new users to pay existing users for payment for instance a new user who signs up and decides to donate $100 will be matched with existing user to receive the payment then at the end of 30 days this new user must have gotten his previous donation of $100 mature to $130 which is 30% of whatever donation, the user will now be paired with a new user or existing user who decided to redonate .........the cycle continues. This matching system should be able to run automatically. It should have a robust admin back end where admin can monitor users, block them and delete them. At the back end we should be able to assign how often we will be matched with other users to pay us in other words we can have super admin privilege to request help at any moment. We should be able to confirm the payment so that these users can receive payment from other users. I need this up and running in a week. Offshore bulletproof hosting preferred.