I checked with a company that installed galvanized garages. Guy offered to sell me a used one. Then noticed my pick up, asked if I had a trailer hitch and said if you remove it you can have it. He got calls all the time to dismantle or move garages.
I put mine up on curb stones (needed to be a little taller anyway), the only zoning requirement, was for the foundation and standard property line clearances. No foundation or slab, no problem. Did the whole thing with square patio stones, curb stones and a couple of truck loads of sand. Been there for close to fifteen years and even survived a small tornado that knocked down a 60 foot pine tree right next to it.