I want to create a javascript to search multiple travel sites for the cheapest hotel

I am building a website to sell hotel rooms, and I want to write a javascript to search about 20 travel web sites for the lowest price automatically and then return a value to my site. Essentially I want to make sure that the price offered is lower than the competition, and I want to know if there is already a product out there that will do this, or if I will need to write something myself. I am running short on time and need a quick solution. Any ideas on this would be appreciated, Thanks.