Off the ground is good for ventilation, possible storage, and to keep critters out. Blocks or 10’ beams so you can level easily from side to side. Front to back doesn’t matter much. But draining to the door is probably a good idea. And room for a jack under there to shim after settling, bottle jack or heavy floor jack.
If it gets hot there, scrub roof with dawn and Henry’s elastomeric cool roof paint. Careful, it’s easy to step off the long narrow roof.
there are often/normally steel loops on the top inside edge (see photo). They can be used to hang shelves. Old cheap aluminum ladders work pretty well covered with plywood.
The new one trips have a vinyl floor that is nice. If wood, treat it before use. Or not. The wood is an inch thick. And takes tons of abuse. But the one trips are pretty nice when they come in and you might want to coat it.
If you care, there are different wood treatments on the floors. The old stuff was bad in a 1950s kind of way. I think the treatment degenerated into something even more toxic than the original. The newer ones have tallynium? No so bad.
The cast corners will accept a large chain hook, I think from the bottom. Then put the shackle end out the side. It makes robust tie down point.
Double doors and high cubes are nice. And that Costco shelf just fits sideways if single door.
2” polyiso sheets can make good insulation. Easy to install. The spacers are for my Mylar layer. I’ve got heat issues you may not have to contend with.
