Hate to say it but caveat emptor. (Let the buyer beware.)
Did you check it out before putting it out? It is possible somebody simply damaged it on the property. I recently changed one of my machines to 50¢ for one of the heads, and somebody didn't see the new price, and broke the mech out of anger because it didn't take his quarter. Doesn't matter how well it's built, somebody can break it if their sufficiently angry. It's generally a good idea to keep extra mechs on hand. I was able to get the machine back in service the next day.
I had a cheaper plastic machine out that somebody got angry, and hit the top of, and the whole thing just broke, spilling out candy and coins. At least the people working there picked up all the change for me, though they didn't call me, and waited till my next service, which really sucked considering I only lived a mile away from this location.
You could contact the seller. But make sure it was a faulty mech, not damage from an angry customer, or some jerk intentionally damaging the machine.
You can find them for about $30, more or less, used. (At least that's what I am seeing online right now with a simple search.) If your willing to put them together, there is an eBay "Buy it now" sale for 6 mechs for $52 plus $17 for shipping. (That's $11.50 each.) He does state that you will need a security screwdriver. It would probably help if you have taken a few apart before. Not a bad idea so you understand how they work, and can fix them, or rebuild one from two non-working mechs.
http://www.ebay.com/...sd=131565870560
