After much planning and considering, the world's most supportive author spouse and I purchased a 10 foot by 20 foot shed, which we're fixing up to serve the purpose. I'll post pictures of the work in progress.
The starting point
Loading up on supplies at Lowe's
So far the place now has heating/air conditioning, temporary power, and several things bought, waiting to be installed. Stay tuned. This is a work in progress that I'm eager to see completed.