....the Registry of Motor Vehicles WILL charge you sales tax. If you don't believe it, fine, but thats just the way it is. It doesn't matter if you bought it from a dealer, private party, or whoever. When you bring the car to get it registered you will have to pay sales tax on the price you paid. And no....you can't say that you paid $1, or anything like that. They go by the current book value. The only way you wouldn't have to pay any sales tax on a car that you bought, is if your state doesn't have a sales tax (i.e. you live in New Hampshire).