What's it like pulling over airplanes and helicopters? Or we're you like the airborne highway patrol guy flying the planes looking for speeders in afghan or Iraq?
Seems like a lot of liability to open a shop where anyone who doesn't normally work on their own stuff can chop their fingers off or drop a car on their head. I bet insurance would be crazy high, especially in California. It's a good idea, but the red tape....... Maybe a motorcycle club or car club has places like that for members to work on their things. Ever watch the devils ride? They had a shop with a bar!! But it wasn't run like a business.
Also, you can look at business parks with a garage and loft style living. Some are artsy fartsy, but worth looking at.