I fairly regularly drive 400-500 miles over two days when going to Maine. I cranked out 1500 miles over two days once, I was ready to pass out on the last day, and on the flight home slept from the time I sat down to after landing (it was a short flight though).

Shortest, I put about 5 miles on a rental. My car was in the shop after a minor fender bender. Enterprise picked me up, I drove it back home, and then used that as excuse to drive the Golfer's car for a week and made him drive the old Jeep. (his was a new Jaguar XF). I can say that was the only time I didn't fill up a car and didn't worry about getting charged for it.