Development of new e-commerce marketplace

Development of new e-commerce marketplace, where different retailers can add and sell their products. The idea: One stop shop. Buy products from hundreds of retailers at one place. All transactions shall go through my cart and payment system. I want a web store solution where different retailers can upload their products and sell it through my web store. Every retailer must have an account of their own where they can manage their products. The retailer must be able to upload products through a simple excel import, get rapports, change products, add personal information, etc. Every time a product is sold the retailer must also get an automatic e-mail with a pick list / order slip (with customer name, address and the purchase related to the retailer). The retailer shall only see its own assortment and be able to manage this. I need to have an admin account where I can manage all the retailers, fees, commissions, rapports and see all orders. The system must also handle all Nordic payment solutions like Payson, Klarna and PayPal. It also need to be able to handle all the languages in the Nordic countries (and English). Preferable this is made by developing a plug-in to an existing open source, CMS system. Is this something you can manage? Send me an offer and I will send you more detailed information about the project. After that we need to book a phone meeting and go it through over Skype or similar. Be aware, this is not a onetime project. I will need a lot of support and development of the platform over the years to come. I would prefer a fixed price for this project (or a maximum price) and then an commitment for hours during the coming year. It is not exactly the same but you can get an idea of what I am looking for by looking here; [login to view URL] The site should be in Swedish at start, but handle all nordic languages + english. Please get back to me and write: Are you interested in this project and want to know more? How would you, from the information above, do this? Existing or new CMS system? Witch one? Questions? Time Frame: August - September