Just be aware if you bury one, they are actually not designed to take pressure on the walls or top aside from the strengthened corners and beams. In other words, they are great for stacking other containers on top of, because the points that carry the weight are strengthened. They aren't designed to withstand the pressure and weight over every square inch.
The other thing you need to do is seal the metal against corrosion if they are underground.
I've seen this done, it just takes a little prep and extra work. When I have the land and space, I will be using these to my advantage, for sure.
Roger that @KayTwo! I'm not the engineer on this project, just the guy with an excavator. I know that sealing/corrosion will be dealt with and will pass on your info about load. The guy doing it is a brainiac and is likely aware of that. I did dig out for a full blown underground bunker a while back and that guy did an actual poured concrete slab, filled and reinforced cinder block walls, and engineered and rebar reinforced roof. He has full electric service with a backup genny served by an underground prop tank, and full bathroom with shower and toilet with a macerator pump. Pretty cool setup. He is now ready for full-out war, government intervention, the zombie apocalypse, or 4 inches of snow - whichever comes first!