Online Customization of Products by customers

We are looking for someone who is able to help us create a website which would enable users to upload files and customize. Users will be able to then customize products using their uploaded file on the product and preview with zoom. At customization they will be able to choose different colors/add colour to the products and add text. There will be about 4 different products which can be customized. After the customization the user should be able to checkout or save their project in their account. After the customer has completed the process we would be able to easily view and retrieve their order. We currently have Magento installed however we would prefer to use Wordpress if possible. We are open minded and will consider other suitable alternatives that might be best suited for the project. The customization and designing script will have the same functionality like the following websites:- zazzle, cafepress and [login to view URL] The script can be done using Javascript/AJax or Flash Action We would prefer to see a demo of the site from bidders or an authenticated portfolio of other **similar websites that have been completed**