PHP and Paypal

This is an on-going project, so if I will be happy with the results, I will be a returning customer. Build a small DB with a few fields: email, password(SHA1), Credits(int), Credits Used(Counter, int),Plan(char *), Date Created (Date), Valid Till(Date) Page: Charge according to few simple (subscriptions/one time payment) plans, and upon payment received notification by Paypal, go to step 2. 2) Add credits: Add to DB: Adding user to DB once the payment had received, with the according credits/plan. 3) Query credits page: By email & Password -> Response with credits counter. 4) Reset Password -> Sends link to the user email with a valid session in order to change his password.