Affordable Motors - Felix Sanchez Took my car in on trade and Put Stop Payment on Check for payoff and refuses to pay off my trade. Miami, Florida

I traded in my car and bought a truck from Felix the President, Owner of Affordable Motors, under contract that they would pay off my trade.  This was in July 2010.  I called because I hadn't received my new tag and title yet, well they forgot to mention they dont do the tags anymore you have to do it yourself with the title transfer they provide you, so I had to wait a week before they mailed me a  new temproray tag, and be out a vehicle because it was the nice police officer that pulled me over to tell me my temporary tag was expired and let me go with a warning. 

The title transfer takes a couple of weeks, so 3 months later I still dont have a title transfer, I still make payments on a car I dont own.  I finally went to DMV and they called Affordable Motors and said they were going to file a complaint, and what do you know I have a title transfer 30 minutes later faxed right to the DMV, with a transfer date from the previous day.  I now have a tag and the title is finally in my name for the truck, my problem now is they refuse to talk to me on the phone, they hang up, and now they will not pay off my trade.  The back of the contract says we can go through arbitration and use self-help remedies such as repossession, so I think I might have to do that to get anywhere.