But why is he tight with money? Can he show you the actual bills of where all his money goes each month, not just him saying that he doesn't have enough? I have family members who are freeloaders, and rarely can they actually provide proof of where their money is going--because if they showed us what they were *really* doing with their money (hoarding it/spending on personal stuff) nobody would help them out.
I dunno, again I'm not trying to be mean, but watch out for yourself. I hope you have a plan of what to do if he doesn't start making changes. Good luck.