I'd say they were renters. Most homeowners don't shit on something they've worked hard for.
To help ya in the future, if this becomes a problem with either this house or another nearby, I'd suggest something that I've found useful:
When you see rental properties nearby post their phone numbers on the rental signs, write them down for future reference. The property management or private owner usually can be contacted and notified of issues. Property records are great and all, but when it gets to the nitty-gritty, I'd rather have a more direct contact I can advise of my own rights
There are several rentals in my neighbourhood and if there are problems with the new renters on the street, next door, whatever, I plan on calling them and letting them know that they've let losers move in and as a long-time owner, I'm not putting up with the BS.
If they've rented to section 8 applicants, they can only live there for 2 years maximum. Also, they cannot allow drinking (yep, ZERO alcohol) or drugs. The Owner/Prop Mngt Co can lose their funding if anyone in residence is found with either.
Know your code-enforcement number, too, for your area. You get someone who will write tickets on them for even changing their oil in their driveway, and you've found a champion for your cause.