Customer to Customer Online Store solution

Hello, I've been searching all over the internet for C2C online store without success. So probably a custom made e-commerce site is needed. Basically I need an online store where users can post their stuff to sell and buyers buy either directly from the seller (they contact the seller by either messages in website or phone number, and transfer money without my intervention, something like craiglist) or the transaction goes through me and I act as an escorow service or middle man and release the money when the buyer is satisfied. There will be custom fields that the seller have to fill when displaying each product mostly text fields. There will be also some paid services like display your product on the homepage etc that need to be implemented. Site need to be Right to left direction and in Arabic. Design is critical and must be extremely good. I will prefer an offer that will modify an existing e-commerce solution than building brand new.