Thanks for all the replies. There seems to common agreement about most things and none of them are things I hadn't considered or realized. He's only here for a couple weeks; I would be crazy if it was an open-ended stay but it's not.
I want him out ASAP and we are all working on finding him a place. I don't say ASAP because of the inconvenience and risks to me, but for his own recovery. I believe I am the last family member that is willing and able to help in terms of a temporary place to stay while he finds the next place. As someone noted above, there can be a fine line between helping and enabling. I am hyperaware of this.
He won't be getting as much as .75 from anyone even for a soda. I'll buy him one, but we all know not to put cash in his hands.