I want to provide quality housing at an affordable price and improve communities.   

“She’s the best tenant, so clean, blah blah”.

Even the cleaning service is paid by the guests.

Fill any holes they use to get in , bait traps outside , snap traps inside , clean up trash and debris around the house . 

Since I'm not a lawyer and I don't know what state you're in, you'll need to find out if this property passed to this guy automatically because a living trust was in place, or if it needs to go through probate before he gets it, or if he was a joint owner with the sister.If all this is clean, then you should be able to buy it from the guy.

Now, the same is true when selling as an investor - being the most expensive home in the area is often not a good thing, even if your property is higher quality.

Literally zero redeeming qualities and not even a good financial package.

Because you described your tenants as "slob", I think you need to have a serious talk with them about maintaining the house clean and free of bugs.

If it were a few months ago I'd say head out to a few FAR (Fresno association of realtors) meetings and let them know you have quality flips coming on the market soon, but Since we are starting to tip back into a buyers market that may be less effective now.  

Having someone change sheets, clean, organize, etc makes a lot of sense.