It looks like a nice duplex, I did a little detective work from the photo you posted and looked up the listing.

Do some detective work try to find the correct party and their location hunt em down reach out to them.

That way future leaks won't be so hard to detect or fix, plus a small leak won't lead to a bunch of mold before you notice it.

It just took some detective work to find this opportunity and track down the owner that had left several years ago and wanted nothing to do with property.

Another weirdness that you may or may not face...many of the homes were continually having big wet spots appear in/on the slabs, hundreds of people, were calling leak detection services, thinking an underground plumbing leak was causing these mystery wet spots.

I had a career as a Paralegal before getting into RE.Instead of “getting playful in the dark”, hire a Private Detective.

The key to crushing them I believe is early detection.

You can drive yourself crazy trying to play  house detective on old homes. 

The background check I have doesn't include hidden personality traits that are hard to detect that can cause time and money to deal with.  

So, figure out ahead of time how they can pay their rent, as you don't want them to give you a lot of cash, as that could be dangerous to you, if some bad people detect a pattern of you carrying a lot of cash.