I move often, and when I'm going to be in one place for more than a month I buy a cheap $1000 car. Then I sell it, usually for around $1000. Sometimes I take a loss, sometimes I make some money, it's a wash.
But when in I am in town for less than a few weeks, I rent. Always with Enterprise. Never on airport. In fact, I've taken hours of busses from the airport to save $100 on a rental.
I think it's easy. I go in, I sign a few times, we walk around the car and I leave. Done.
Getaround is cute but its too expensive, Flightcar sounds nice, but it amplifies all the problems that Getaround has.
Meh.