Build price comparison site

Require new website built for price comparison of specific services, to be able to source prices from retailers, search, collect, retrieve data directly from retailer sites, update the data in real-time, with tracking tools thus get paid every time a user completes a specified action, for example when they buy something, register with their e-mail address, or click on a particular service offered. After the click through I want no further involvement. As the idea of price comparison is now well established, I suppose merchants will presumably supply their own lists of products and prices providing information electronically, probably in an existing proven format. The data feeds will be imported by the new website enabling us to monetize the products contained in the feeds and therefore earning commissions on click through traffic. Maybe the new comparison website service should scan retail web pages to retrieve the prices, instead of relying on the retailers to supply them. Either way, collect data using proven techniques. I suspect that once the website is up and running, further support will be inevitable, so please don’t bid unless you are prepared for follow-up business.