If you do enough sales of virtually any product buying a car gets easy. It's just a game. When the salesperson says "I'll need to talk to my manager," you just

If you do enough sales of virtually any product buying a car gets easy. It's just a game. When the salesperson says "I'll need to talk to my manager," you just say "No problem. I'm not in a hurry." And when they try to add stuff to the contract at the end, just say "No."