I mean you interview the person and family why can't you meet the family dog.  

If they have 1 dog they will pay 800. 

Good credit - two dogs and a cat.

Bird-Dogging, Capital Investing, or Handyman Services are all possible places to start.

Bird dogging is just driving by and calling a distressed property in with no risk to them what so ever.

Barrier fences have gone up and he has a couple yappy dogs to protect his grow. 

If you're seeing lots of dogs, appliances outside, and clutter everywhere be prepared to spend a lot of time changing tenant behavior, which takes a significant amount of effort and should be reflected in the price one way or another.I always ask about the tenants and if multiple homes are owned by a single person to see if there's any red flags.Oh yea, cats.  

Dangerous dog breeds, Umbrella policies and their limitations, previous lapses, previous damage and liability claims.

There are other bird-dogs and wholesalers who are looking for vacant properties as well. 

Your best bet would be to become a "bird dog" or a deal hunter.