I'm weird, but I love buying or leasing cars and negotiating with the dealers. Today it's very easy to find out what the value of a car and a good price, including options.
You must buy on the last day of the month - preferably the last day of the quarter. The dealer "invoice" is only one piece of the dealer's income. The manufacturers incentivize the dealer with variable compensation based on, in part, the number of units sold during the month, quarter and year. Starting to get the picture?
You will be able to buy a car for under "invoice" and many times substantially less than "invoice" if your timing is correct. A dealer can take a "loss" on your sale and still make good money based on their incentives with the manufacturer.
Buying new is like taking candy from a baby - I love it. Buying used from a dealer is a different animal.
No rebuttal - just passing on info.