Create an app to integrate our websitewith eBay (and/or Amazon) stores

we need the tool to integrate our website with eBay (and/or Amazon) stores, includes a fully customizable eCommerce storefront and sync with an existing site. - Multiple channels (one of the most powerful eBay & Amazon integrations) - eCommerce storefront (fully customizable, SEO-friendly ) - Invetory management (stock levels & pricing update across eBay, Amazon and website) - Centralized order management - Bulk uploader (handles 150,000 items w/ images) - Carrier shipping integration - Process orders, print labels, invoces, packing slips and pick lists out of the platform + Multiple users supported (the whole team can be logged in at the same time)