This is a very honorable goal. What I gather from your question is your goal of finding damaged homes and renovating them in order to offer housing, am I right? Finding damaged homes, easy. Renovating damaged homes, easy. Turning this venture into a sustainable model of providing homes for the less fortunate, not so easy. I recommend discussing your plan with a non-profit that has some experience with this type of venture. I would also lay out a plan with a good attorney and accountant.
If you build it, you will want to keep it healthy.