find soundtrack with the cheapest licence Many websites provide licensed music/soundtracks you can use. For example, I like this soundtrack. It comes with a fixed fee of $49. I am wondering, there must be some other provider I am not aware, that sales the same licensed soundtrack at a lower cost. ($49 may be little for large corps, but not for small business owners).

How do you find the cheapest provider for the exact soundtrack you like? Are there any websites that search the web for the lowest price? I hope this is not off topic, because finding quality music is essential to video production.
As far as I'm aware. There is no 'soundhound' or Shazam type app for royalty free stock music. Usually these websites require that the owner only sell the music on their website rather than a competitors. I'd say the likelihood of finding the same song another site is slim. 

With that being said for cheap stock music I always go to audiojungle and for the higher budgeted jobs I go to musicbed. Sometimes I will check out extrememusic just to establish what the client likes; but that sites tends to be studio-only unless you are willing to fork out $$$.