No I did not pay sales tax at dealer but MVC to avoid the documentation fee. NJ sales tax is 6.625%. All states that I have seen so far according to my google-fu must pay sales tax on the sales price and rebates. It is the price of the car minus trade in. They count the price including rebates. Trust me I told them what I thought about this... maybe NJ does it different.
https://budgeting.thenest.com/taxes-...-car-4018.html
https://smallbusiness.chron.com/sale...-in-62364.html