Hey there Marine06. Unfortunately the equation is not that simple. Say the MSRP is $20k and the total of your payments is$26k here would be the rough breakdown depending on where you live.
$18k--mfg. (invoice 4 car)
$1,300--fed gov't (taxes)
$600--state gov't (registration)
$26k total of payments.
Now that's a vehicle sold at MSRP. That is also obviously not with exact calculations of tax, tags, or intrest but it's a decent guess. There really isn't a whole ton of profit in most cars. That is also the beginning of the profit that the dealer collects. Then you pay for the lights, the electricity, the salesperson, the manager, the cost of the cars gas, cleaning, and that also has to pay for the "rent" the dealer pays monthly to have the car at the dealer. if a car sits for two months it can eat up upto $500! It's not a simple math equation.