From what I've seen the most desirable vehicles on used car lots are former rentals. Maybe slightly behind cars that fell off of a lease. There's always the stories about people who rent cars so they can thrash them in street races or whatnot, but really most rentals are for businesspeople who need to get around a city for a bit. The companies usually try to keep up on the basic maintenance items as well, which is not always the case for used cars. You get a fairly new car with higher than average but not crazy miles for a decent price.

These Teslas should also qualify for the $4000 used EV tax credit as well, which could make them quite an affordable option.