I've noticed that whenever I try to open a PRO thread on my iPhone, using the BP app, the app crashes.

Get the power and water turned on first to check for leaks and power problems. 

The walls were then cracked and the roof developed a leak.

I also inspect plumbing to assure there aren't any leaks, maybe filter replacement, co and smoke batteries.

I phoned the water department again during the week of Thanksgiving.

thank you @Alex Deacon and @John Leake

The major one was the part of the water main running into the house sprain a leak, that ran for some weeks, and caused erosion of the under-soil.  

I've got two short sale properties approved recently. 1 for $60k below the appraised value of 200k (and asking for more now since there's a leaking tank and they are actually willing to credit me more now too.) and another which appraised at 225 at 155.

So even with no leaks a landlord gets hit with more expenses per unit.Rents have been in bubble phase for apartments.

The potential liability includes the possibility that the tank leaked into groundwater, perhaps groundwater extending beyond the subject property boundary.