Clone of paid-to website

I looking to create a website that is very similar in function to Cashcrate.com. In particular, the website should be able to track when customers have completed affiliate offers and credit their account with a balance. Users will be able to choose offers to fill out and will get paid a small fee for each one. Website will require a membership sign in along with the ability for users to see an account balance. More details will need to be discussed, but this is the major focus of the project.