Word of advice - when I plan to murder someone, I don't post about it here, in case I need to plead self-defence later.
Good.
Just think it all through and make sure you're not relying on money coming back to you, as it could be a nightmare to get it. If there's anything you're unsure of, just...
How many more months of rent have you got to pay? Ask for the money for the boiler etc now, and don't pay the rent until you've got it (cleared, not a dodgy cheque). If he has financial problems, you don't want to pay all your rent and then find out you can't get the money for the work you did...
Who paid for all that? How long have you been there?
If it's you that paid, I've got a place that needs doing up - sorry, I mean I've got a lovely home you can stay in for the rest of your like, anything to help out a fellow fan.