Design a simple, catchy Classified Ad/eCommerce website

I am looking for a designer to design a classified ad website selling digital content (mostly apps). 1) The website will display products for customers, and also have a section for third party developers to upload their products. 2) The website design should be made for 3 form factors: computer, tablet, smartphone. 3) The website will carry un-intrusive adverts and so ad locations should be strategically designed into the website. 4) Simplicity of design will be highly cherished and designer should assume that users have poor internet connection 5) The designer should have a full understanding of classified ad sites, eCommerce websites and appstores. To bid, please provide evidence of previous work, especially of a classified ad website or an eCommerce website. Happy bidding