Lye soaps require fat, from what I understand; otherwise, it's just lye. It's the fat that would be the trickiest. Every animal that wasn't under armed guard would probably be killed and eaten in less than the first year.

Plants are interesting, but it might be difficult to grow enough.

Toothbrushes are more important than toothpaste. It's the brush that does the work. The paste just adds a little fluoride and scent.

Okay, homemade soap if you have fat available, soap plants, storage of commercial soaps, and soap rationing. Anything else?

Sue