I'm not quite sure how BigBuy.eu and their dropshipping store works. At SaleHoo, some of our suppliers provide a CSV file for their products that you can upload all at once to your SaleHoo Store. Much as to what you've described here -- as easy as that and you are almost all setup!
We're also offering combo packages for SaleHoo Wholesale Directory, and SaleHoo Stores with our Standard and Premium Store Plans.Link hidden: Login to view
Hope this information helps.