simple e-commerce project

Hello, I am looking for an e-commerce system (PHP with MySQL) or a PHP programmer to build a simple online shopping site. The major functions of the site will include a shopping cart with Paypal payment gateway, member registration and log in authentication (member can view and update their information), and back-end admin management (view, modify and delete products or members; view order). The code must be simple to understand since I will need to maintain the site by myself later on. Good graphic skill is necessary to build the site. We can provide some mock-up images. If you have already built an e-commerce system with our requirements, we can also consider buying it with proper customerization. We also need the clear documentation (25-30 pages) of how the system design and implement. Please post your portfolio for consideration first! Thank you!