In these Covid times, a fair amount is messed up. I was gonna mention Lone Rock, sounds like another Covid casualty.
There are the courtesy cars scattered around. Boscobel, WI is a nice airport, cheaper fuel, last there than had 2 courtesy cars. Mineral Point & Plattville had cars.
If going soon I’d try to stay away from MSN & MKE. Watertown had walking options, not sure how much is open.