All I can do is think what I would do if I was in your situation. I would hold off on the homeless issue until you have a stable home environment. Anyway, until it comes to the point that he should know. If after a few times you realize that you will continue to see him, then let him know. You can tell him from the beginning, but at a time when he does not know the kind of person you are, it might be hard for him to see past that. Just see how it evolves and try to stabilize your living situation if you can. Best of luck and have fun.
Sesquix