She complains about everything, has a very obnoxious attitude, and has been just plain miserable to deal with.

The PM found a water leak in the kitchen area (upstairs) and water stain on the outside of downstairs bedroom.

.- You mentioned water in the panel board and wet/corroded breakers.

Or a water line could freeze and burst in 2 months and create a 3-4k repair shortly after buying.

when assigning an inspector make sure they test the water.

Usually the numbers from brokers and listings are hopeful, misleading or just plain wrong and you need the ability to find the right numbers and underwrite from those. 

Unfortunately, we have just learned about a water damage caused by the people living upstairs.

@Arwin Nassiri Be sure to do your due diligence when considering raw land, and consider particularly the cost of getting water and other utilities to the location and whether you can actually build on the land at all - any structures or improvements within 25ft of a Joshua Tree will be difficult, expensive, and likely impossible in most areas - and you generally can't move them either. 

But, if I was brand-new with no lease or idea what to do and/or no time, they are decent enough to keep me out of hot water.   

Just use plain old english.