Someone told me a long time ago that anytime someone asked for a favor from me, I needed to respond by giving them a task to do (to show good faith/do their part). Never volunteer to help someone without them doing something first on their end. I think you are applying that concept by asking him to contribute money/do the maintenance/etc. I am still surprised by how many people will walk away when I ask them to 'do their part' but it quickly reveals those who are trying to get something free from me (time and/or money).
Overall I think I would so the same thing you are doing. It is always good to help out family and talking to him about finances is also great. Not only are you giving him a fish but you are also trying to teach him to fish.