I don't think I could stress how much a ferret can get into things. Mine can open sliding closet doors. He gets behind the fridge and then he has access to all the space under the cupboards and behind the stove and dishwasher. I have to keep a board blocking the side of the fridge.

Litter box training is very hard for a ferret, not like a cat who naturally goes in litter and covers it up. I would not tell any potential owner to expect a litter trained ferret. This gives people the wrong impression from the start and they're in for disappointment or getting rid of the ferret. The ferret will pick corners they like and I just put a flat piece of plastic in those spots for easy cleanup. I also leave him in the bathroom for a minute when he first gets up because if he goes on the hard floor I just have to wipe it up with tp and flush and its gone.