The BH is easy enough to lower to get in ... until you forget . I opted for 9 ft doors, wish I had gone taller. My tractor fits in easily without having to think about it, but I have to be careful with the snowboard racks on the truck.
I'm in the Ottawa region, QC side. I had to specify, on my permit request, that I wasn't doing a foundation and the permit didn't get rejected. So all good.here, Hamilton,Ont bylaws state it HAS to be a real foundation NOT floating slab. So go down 4', footings,wall in ground, then build up from there, floor slab is 4 to 6" concrete.
A floating slab ,say 4" thick, will have the perimeter dug deeper ,say 12" and about 12" wide to 'lock' the slab to an area..so it won't move .far,far away.
How it's built depends on the bylaws of the town you're in.....