Secure Client Area for viewing Edits

We are doing the website for a recording studio and want to have a client login area where clients can log into there own secure area and view various versions of edits that have been done in the studio. The client would login from the website to thier own page. This page would pull the various edits (probably as Quicktime movies) from a database (mySQL?). The client would then be able to select which edits he would like to stream or download to view. This would be charged for so it would be neccessary to have a record of who has downloaded what and when. An administration system would also be needed to set up new clients and administer the system and the records in the database. The whole system would have to be very secure and would reside behind a firewall. Finally if you are intrested, what kind of turn around time for this would you be able to do and at what price?