my dad did this for a long time and it was ok, never really gained that much money, jus gained some quarters, fake coins and free drinks when he wanted. He was really going to get into it and sent $10k to get more machines to this one company and then the company never sent the machines and that was it to the soda business.
he just left the machines in this bank andnever went back to get it, we hav 2 laying in our garage.
oh and one tip, if you can get a quarter and pound them until they are the same size or roughly the same size as a dollar coin, it would register as 1.00 but defacing currency is illegal.