Yep, I appraised one that had central heat and air, a restroom and office (finished out) and the floor was coated with a TUFCO resin industrial floor (he worked for them.) Overhead door, GDO, finished interior, insulated, etc. You can spend some bucks on it. I know a guy also who built a 1 bed apartment in his shop when single. He remarried and built a new house on the lot next door (he owned a number of lots there.) The shop is great and he can spend the day in the apartment without tracking grease into the house, etc.