Create a website or add functions to existing opencart website.

I want to create a website on which visitors will be able to see prices for products from multiple shops. The items are everyday items like milk, bread, fruits .... Once a person opens a product page, he should see the prices from different shops (need a place where I can add new shops (this can be added via phpmyadmin, does not need to have an area in admin panel)). On every product page, there should be an option for visitors to add new price that they saw in their local shop, also there should be an option to add new products (visitor adding, not admin). This can be done by registering or by guests - we can discuss that. After each change that the users/guests make, the changes should be reviewed by admin before posting on the site. Each of that products can be added to the basket, at the end, when user clicks on the basket, the basket should show all the products listed and prices from all the shops listed in collumns. In the end it will show which shop is the cheapest. The checkout feature will not be used. For your refference, you can check this website : mysupermarketXcoXuk The work can be done in opencart (which I have installed atm) or u can make your own script if you wish. I need my opencart website to have prices from multiple diferent stores, like this site has : [login to view URL] Click on a product and then you will see different prices from different shops. When a user clicks add to cart, the cart should separate prices from each shop in a collumn, so people can compare where is it the cheapest to buy the things they need. No checkout process needed. It needs to have ability for users to add new products, and admin should review them and approve to be listed on the site. If you are interested in doing this project, please describe how are u planing to do it. All freelancers will be considered.