I had verbal agreement with dealer to buy a new car and trading in my existing car. I specifically said the the only down payment is the equity on my existing vehicle. We verbally agreed that I will be paying 375 per month for 60 months. They had me sign the purchase contract not knowing that they included a 3500 down payments not the contract. I signed the contract. Dealer did not collect any down payment at the time of purchase. 3 days later they call and said I owe them 3500. They told me that if I don't pay them, they will not pay the remaining balance of the loan from the vehicle that I traded. Or they will even sue me. Do I have the right not to pay them the 3500? What should I do.