Not to come down on you too hard because I assume you have good intentions, but as other have said, rehabbing a rundown building will do more for you (if everything goes right) than it will for the city.
In other words, if you want to invest to make money, go for it, that’s your choice (but please don’t be a scummy landlord, we’ve got plenty of those). But rehabbing rundown or abandoned buildings isn’t a terribly effective or efficient way to “help” the city.
Yes, the more properties on the tax roll the better. But that’s a small piece of the puzzle as far as Newburgh becoming a great city for all of its residents, no matter one’s economic class or background.
Newburgh needs affordable housing, not necessarily renovated units that are going to rent for $1,200-1,800 a month or whatever.