There are things insurance excludes like flooding, toxic spills, sink holes, earthquakes, unless you buy a ton of special (and expensive) riders for your policy.  

Best public schools in the country, lowest insurance rates (because Maryland has low risk for blizzards/hurricanes/earthquakes/tornadoes)) and lots of military bases and permanent federal installations like NASA, NIH, FDA, Census, SS Administration, etc. that make it recession resistant. 

It's the darkest before the dawn moment for large international cities that have withstood wars, pandemics, terrorist attacks, earthquakes, blizzards, financial ruin etc.

This whole time I have heard flood,fire,earthquake.

While there are earthquakes, I am not aware of any damage ever caused by an earth quake.

Few bugs, everything within a 6 mile bike ride, no tornados, hurricanes, or earthquakes.

Earthquake insurance is separate and prohibitively expensive and almost no one has it.

Although some 3rd world countries like Haiti sadly are maybe currently as bad off as during Great Depression. 

Not to mention vacation areas can get hit with any number of devastating disasters like fires, earthquakes, hurricanes, terrorism, flooding, tornadoes, air travel disruption or even just economic disaster.

As an example, following your guidance - if I have 3-4 highly leveraged properties in the bay-area, minimal cash-flow and if an earthquake (1989-like) were to cause major damage - then I'd be SOL. or is there a way out?