Build a travel meta search engine like Kayak and Trivago

I am planning to build a meta search engine for hotels and other travel products, something similar to Kayak.com. Some work has been already done. See [login to view URL] (Presently you can search only for hotels in London UK.) To continue I need to add third party APIs from Online Travel Agencies, (OTA) like Expedia, Priceline, Orbitz, Agoda, etc. However, these sites generally don't want to deal with sites that have no traffic. We can't have a traffic without inventory. If you have a solution to this problem or know where to get APIs and know how to finish the project I'd like to hear from you. Please let me know if you have done similar works, with links and the contact person of the site for me to verify your claim. This is a fixed price project. However, I understand you can't give me an accurate price until we discuss the project in detail, so just put any price as price holder. While I have no budgetary restriction, I know what this project should cost and will not pay more than the fair value. Shooting a high price is often indication of lack of understanding the project. Thanks and look forward to hear from you. PS. I have had my share of dealing with unscrupulous developers. If you treat your clients the way you want to be treated, we can be working with each other for many years. If you see your clients as cash cow, please seek another prey, someone who is more novice. You will be wasting your time and mine.