It seems the bar is "high" enough that the danger is low of good landlords having bad luck will make the list.

Dangerous  Neighborhood 3.

The first mindset is dangerous, in my opinion, and does not solve the root of the problem with these folks in most cases.

as far as a boa etc.. no it'snot necessary.. or a python etc.. they're AWESOME  but big and CAN be dangerous,  venemoids and constricting snakes are often illegal in many areas anyway.  

Which again is bizarre to me and very very dangerous.

I know just enough to be dangerous (mostly to myself). 

Buy safely cash flowing properties and you will survive the crash, in my opinion trying to time market is very dangerous. 

The danger of doing this improperly yourself, besides not having current and accurate financials as others have noted, is that you are likely miscategorizing items and possibly losing out on deductions.  

I would do a thorough search of every piece of dry wall and any other surface that is around the shower and go look at it in the attic as well.Generally speaking there is only a handful of mold types that are dangerous.

If the tenant is a threat/danger to others, the Landlord should be able to get rid of him.