eBay type site needed to be built

We are looking to build and eBay type site for the contractor's business. It's kind of like having ServiceMagic's service ([login to view URL]) with eBay's look and feel. The concept is as follows. 1. A home owner decides that they want to remodel, redesign, hire and interior designer, a landscaper, etc. 2. The howe onwer logs into to his account on the website 3. The home owner list his project on the site given a general description similar to the function within [login to view URL] 4. Users have the ability to upload details of the project including pictures 5. There are x days that the project is listed 6. Contractor looks at the details and decides to provide an estimate 7. Contractor can ask for more information by sending and email, the email address is masked and the communication between the home owner and the contractor is available online only. 8. Once bidding is closed the home owner is sent up to 3 bids with contactor details 9. Integration will be necessary to something like escrow.com to allow for payment of project