build me a metasearch ecommerce and marketplace website

I need to create a meta-search engine website for marketplace and E-Commerce stores (like a metasearch kayak for travel booking) and aggregate the results and show them in an easy to consume, so that the user can make a choice based on price, store, delivery details etc. This website will act as a comparative engine for european e-commerce and marketplace websites (like Amazon, ebay, yoox, asos, decasthlon, [login to view URL] ecc.) in the category of electronics, mobile device, books tickets, fun ithems, clothing, shoes ..more extended as possible . This website not only searches and lists the various websites which offers the selected product but also highlights the website which offers the least price. In the backgroud I need to be able to add more API. to the end i need a register/login tool fo user with email, facebook and gmail. thank you.