Bob,
There are a few places like this off Green Meadows behind the Walmart on 23. It's north of 270 but is close to you. Also there is a small property just west of the railroad tracks in downtown Powell. I know a couple people who rent spaces just like your pic. Rent is relitively cheap, you have space for several cars and a bathroom. Typical mini storage units do not and most won't let you work on cars on site. Check out Marcus and Millichap, Grub and Ellis, CBRE etc websites to see who has space for lease. If there is a certain place you find, PM me and I can look up rents for you.