There is already a lot of really good information on this forum about low-income investing. My two cents would be to start by researching local programs at the county, state, and federal levels that provide funding for these types of commitments. You may be able to access grant money upfront or a 0% loan, tax relief, and other benefits.
However, as @Nathan Gesner mentioned and I agree it is a kinda dumb and rigged syteam where very few people in the world really want to solve the problem. AKA {they lose their job}. A significant portion of the available funds and units are held by larger organizations that have the resources and experience to develop new construction projects and leverage their numbers for cost savings. While it's important to keep this in mind, it's not the only way to approach low-income investing.
Non the less, In the meantime we can utilize the available programs to the best of our abilities to provide low-income housing. By staying informed and being proactive about seeking out funding opportunities, we can make a difference in our communities and help to address the critical shortage of affordable housing. I hope to join you in this real estate nietch and grow a profitable business that help many communities.
best of luck