Does Wholesaling make sense?

[Richard Ayvazyan]

I'm curious to understand how wholesaling works? I understand how it works but want to know how wholesaler's make money? If you are a wholesaler, you get a property under contract (by putting the Earnest Money Deposit) in escrow then you have a certain amount of time to find an buyer/investor to assign the contract over. Right?  What are the fees you charge on top of the price? Is it a flat fee or an percentage? If you don't find a buyer by a certain period, do you loose your deposit?  

Your insight would be greatly appreciated....