Build an Online Store

I am looking for someone who can design a website, where users will have individual profiles. They will be able to list and sell items with description, uploaded photos, pricing, and other product information. I am looking for my site to be similar to [login to view URL] or [login to view URL] I will need a payment system where each seller collects payments integrated with Pay Pal. Also, our commissions will be deposited, so user profiles and accounts will be necessary. Basically, if you can look at the two websites that I mentioned, you will get a good idea of exactly what the project will cost. Please include a timeline also and any additional costs that we may incur. I am looking for an honest bid, not the cheapest one, but the best one.