When I first became interested in metal working I built a small building, 8'x20', behind my garage. I made the building so it could be moved, when and if I ever got to retire to Maine.
However, when it came time to retire I wanted a much bigger shop, so I left the small shop and built a 20ft by 48ft shop in Maine. The shop is above both the garage and the master bedroom. It is a bit tough being on the second floor, but a friend built a nice gin pole for me and I can lift anything I heed into the shop. I have an outside stairway and double doors for easy access.
A shop with an ocean view is really a luxury!
All my machinery was purchased used, most at very good prices. I have an 11" Rockwell lathe with a 48" long 'flame hardened' bed. My mill is a Clausing, with a Bridgeport head on it. I also have a Sherline and Prazi mill
The rest of the clutter is the usual collection of hand tools, and stock.