Zen Cart membership / subscription module

( I would like to here from NETSOLVE ) This project is the creation of a Zen Cart membership/subscription module which will reside along side the regular Zen Cart system. The membership area will utilize the Zen Cart system except all products will equal $0 to subscribers only (Subscribers have paid or will pay a subscription fee which overrides the price of all products which are downloaded). Normal users who have created accounts will continue to utilize Zen Cart's checkout system and will continue to pay per product purchased at the product's set price. Membership subscription system should be a 7 day and 30 day subcription Non-renewing subscribers' account access should expire on the expiration date Subscribers should not have to pay to check out. Instead, their products will be delivered at $0. but normal non subcribers should continue paying normal price per download. I do expect that this system will come with step-by-step instructions example of the type of work i want to be done is on [login to view URL] exactly the same type of subscription module will need to have done same type of work like this before and a catalogue of youre work of same features would be great thank you...