They call that “flipping”. I worked for a guy that did this except, to be fair, he really did try to craft a decent house out of crap. FLIPPERS had a bad reputation at that time but hey, now they have an HGTV show actually called “FLIPPING” something, something.
But this guy never rented to Section 8’rs but like I say, he really did a nice job with his renovations.
I suspect that your guy and his fine refurbished houses are likely the only single homes rented to section 8’rs.
Again....a hunch.
If this guy is onto this and is making money you can bet there are others.