Needed is a clone of [url removed, login to view] or Mobissimo. This site compares several hotel and flight rates from different database sites (through affiliates programs).
The web site visitors gets an offer with different hotels/flights, selects the provider he would like to buy from .
You have to make everything, all I provide is the websites where we have an affiliate agreement with and witch you should screensscrape. One of the most popular site in Europe besides the above is [url removed, login to view]