Some surprises I've had in this area:Sheriff kicked door down in one house b/c they had a warrant from a previous tenantFound a gun in one house (ended up being a BB gun but looked like a 357 revolver)Had tenants leave the house, left all their stuff, and never heard from them again, after living there for only a few monthsHad a water leak in a ceiling that flooded my garage and damaged ceiling in dining areaOn the positive side, have provide safe, affordable, clean housing for some great people.

Walked roof and says roof looks ok , but wood rot in attic from prior leak and water stains on roof but not wet at time of inspection.

She did express to me that there was a leak under the sink.  

But next quarter I had to call the guys about the high water bill & have them check for a leak.

Mold inspector said most of the problem is housekeeping  that he could see, and that there are no water leaks in the house.  

If your roof starts to leak, AC breaks down, etc., you'll have to deal with expensive repairs while hoping your home's appreciation will come out positive.If the market corrects and you have to hold on to the property longer, you could be losing money from having to handle repairs while you wait for the home price to go up.Forced appreciation through rehab is your way to minimize these unexpected costs, not speculative appreciation.

You may have other damages if the water leaked into areas where it shouldn’t.

Estimated rehab is $175,000.I was able to negotiate the price down to $230,000 and the ARV is $600,000, so luckily, there's a lot of meat on the bone.At one end of the house, there's a big leak in the roof and that wall seemed to be sagging as the door in that wall was jammed shut. 

The key to crushing them I believe is early detection.

Next question is what to do to most protect the cabinets and floors from water leaks?