It's going to be a bumpy ride

[Dom R]

Yeah, typically, I think people decide to do the "stand tough" thing, after they move out.

I think that the best thing, is to make his stay while in your home, as NICE as it POSSIBLY can be. make sure he is left with positive memories. no blow-ups, no ....

Then, if you choose to go tough after he moves out, he is left with a heap of positive memories of you, while he is sitting in a (hopefully) empty apartment.