I don't know much about this, but when I visited Japan, I walked aimlessly in the outskirts of Tokyo (Sumida city) until I ended up in a homeless area. They had used old palettes and tarps to build square houses with functioning doors, and it was surprisingly clean. Their shoes were neatly lined up against the walls, they used trash bags and the ground was clean. It was quite a culture shock, because it was cleaner than non-homeless streets at home.