The best idea so far is the C-can in the ground. 8' x 8' x 20'. Not the 40 footer. Plenty to do what you want. 20 footers cost about 3,500USD.
you could bury one an easy 4ft from the surface without any structural issues. Just dig, place, and backfill. You can run all the utilities after it is in place.quote]
I'm looking at shipping containers, the ones they stack up on ships and send overseas. Is that the same thing you are talking about? I want the whole 40 footer, front third will be storm shelter. I can get a used one delivered for 2700.
I believe it would be wise to brace up the ceiling, wet clay soil weighs a BUNCH...