This is a New Jersey Sales Tax Question. I recently (on Monday Aug. 24th) purchased a new car using the $4500 credit from the federal cars for clunkers program. My dealership calculated my sales tax before deducting the $4500 credit. I questioned this and they said it was the correct way to do it. However, a friend purchased a car from a different dealership and they deducted the $4500 credit, then calculated the sales tax. Which is the correct way to do it. If my dealership improperly taxed me, is this sufficient ground for me to void the contract and demand to return the new car and get my clunker back? If so, what if the dealership is no longer in possesion of my clunker? If I can not return the car, can I legally demand to get back the overpaid taxes?