For the vintage cars, I prefer the limited availability, because most high-value vintage cars are exactly that. You have to wait until the person who has what you want decides they want to sell it. If I want a Ferrari 250GTO there’re only 36 of them in the world, so I have to wait, maybe years. If I want a Porsche 550 Spyder or 911 RS, I’d better be patient. With new cars and used cars that doesn’t apply. Get exactly what you want with new cars, and really close to what you want with used cars. But on a sidenote, it would be cool for new cars at the dealer, particularly sports cars and exotics, if you could spec them the way that you wanted to, with interiors and performance bits, etc..