100K Investing
http://100kinvesting.tk/Homes for the Homeless
Look to buy up MFH, generally mobile home parks, gated communities, or similar, that have vacancies. Then work with the VA, Independent Living organizations, and similar, to help those who are in need, getting employed, housed, etc. Thus, not only are we helping the community at large, but by adding tenants, we increase cash flow.
Angel list: https://angel.co/company/100k-investing