Help E-Commerce website

Hi. I am looking for someone to design an E-commerce store for one of my websites only. The store should be able to have visitors sign up as members, post trade, sell, bid or buy options (credit card, paypal ccbill etc). The E-store should be able to have a wider range of categories ranging from electronics and books. Please impress me with your ideas and improvements. Price is between 30-100 US dollars. Once I like your work, I am going to commission you to design my other two sites as well.