Auction Site

I would like to create a reverse auction site. Some examples of sites are [login to view URL], bidclever.com. I don't need all the features of the site. Users should be able to signup, purchase credits (paypal - ipn integration, google checkout or egold), be able to bid and be noticed if they are the current winner. Users should also be able to post comments, tag the item, bookmark it in web 2.0 sites. Users should also be able to see past auctions. Site should also have an affiliate program to refer other people. Admin side should have capability to add new products, set value, auction end time. admin should also be able to see various reports on the current and past auctions. Please post the keyword "excellent" in your reply so that I know that you have read the description. Thanks - Govind