If you have money to invest, you can do some easy good by buying or starting a trailer park, organized so you are selling the lots instead of renting them. Maybe loan residents money for the lot.

Get people to move from predatory rental lots, which they can, and will, with a little encouragement. It won't be a great good, but it is better than letting VCs and bankers hold your money, and you will be able to see the people you are helping.

Maybe put in a school kids can walk to, and a smallish grocery store. Make sure it's on a good bus route, with a county drug-counseling office and a community college on the same route. People want to improve their lives, and will when they can. But American life lately seems designed to grind them down.

Representing a bloc of votes can help get local government on their side, if they can be persuaded to vote for their own benefit.