The M550i sits between the regular 5 Series and the M5, with a 4.4-liter twin-turbocharged V8 making 456 horsepower and all-wheel drive. This 2019 example has the party trick: a Display Key with its own small touchscreen that can drive the car into or out of a tight parking space at about 1 mph while you stand outside. It also carries the Luxury package, massaging seats, a head-up display, and a BMW carbon fiber diffuser and spoiler, in black inside and out.