My garage is closer to 20' wide (would have to measure to be exact) and if I back in the Miata and keep the passenger sides very close to the walls I can get both the Miata and my Ranger or my friend's Dart in and get the driver's doors open without hitting. The garage door is 16' wide.
Passengers (which I rarely have) can't get in or out of them when they're in the garage.
Probably wouldn't work with 2 large vehicles.

