Database driven site

I need a database driven site that is comparable in quality to [login to view URL] The products will be nearly identical to those listed at [login to view URL] BUT WITHOUT THE HUMES AND BERG product. There are a LOT of different products and sizes. Features required are: A shopping cart feature (Purchasing will occur through VeriSign. We will set up the merchant account to accept major credit cards.) There will need to be a shipping calculator added to calculate shipping by product weight anywhere in the USA. 3 different "portals" to enter this site (3 different dealers for now). Each dealer needs to be able to set his own prices, so that if our original price is $45 for a product, one dealer may mark it up 15% (cost x 15%) and another may mark his products up 20% (price x 20%). ALSO a high-volume dealer will also receive a buying discount, so that his prices would be calculated as (discount x cost x markup = sale price). This will be a lot of set up on the database end, but we need this to be able to expand as we expand our dealer network. I will provide a page layout and all photos, web-ready. I will also provide the text for each page. Please be sure to visit the sites I have listed to make sure you understand the requirements for this site. I will also require samples and references. Please indicate if you require a sum other than in this price range. Thank you! Nate