I had a similar thought. But I have carried some large (not $75K large) sums of cash when either buying or selling a used car.
I have a friend that went to a dealership to buy a new van with a briefcase full of cash. He did get the van for the price he wanted. AND he let the dealership keep the briefcase. LOL. Between letting his 5, sleep deprived and hungry kids run around the showroom while they negotiated and the cash sitting on a desk for all to see, he swears he got a great deal on the new van in a very short amount of time.
That’s unusual. That he got a good deal with cash.
Dealers do not want cash sales. They make far more profit on a deal with the financing.
Long story short. If you have the cash to buy a car, great. But don’t bring it to the dealer.
Make your best and cheapest deal on the car. Then go to the finance office and sign the deal. If they want to screw you for a high interest loan, so what? Sign it.
Then pay it off in full with your cash a week later.