Cars degrade in value pretty strongly based on age, not just mileage. For example, a 2009 Toyota Camry with 5,000 miles on it, base 4-Door sedan, in excellent

Cars degrade in value pretty strongly based on age, not just mileage. For example, a 2009 Toyota Camry with 5,000 miles on it, base 4-Door sedan, in excellent condition, shows a Kelley Blue Book price of about $13k (in my zip). It would've been about $18k new. But your point is taken, a great deal of the equity burn on a car is mileage-related. (Especially when you consider that if there are three users of a rented driverless car, it drives more than 3x the distance than would three separate owned vehicles for the users -- it must, after all, shuttle itself between users.)