Do you see any risks in this area from climate change, water, earthquakes, or flooding?

Look for cross or blocking on the joists for earthquake and general stability. 

I just don't know if my DTI would allow for a second HELOC on another property if something disastrous did happen - like an earthquake or something (which did happen here 2 years ago).  

Well earthquake hit on the night of the World Series as we all remember. 

If a home owner doesn't properly maintain their home, you would think an earthquake hit their house from some of the stuff I have seen. 

Or, a charging order may be granted.If you're going the umbrella insurance route, perhaps see if it will cover you for several things including just the routine slip and fall (like mold or earthquake).

Until a new "Robinhood" appeared (it could be zillow or homes.com), there would be not much earthquake.

Or, a charging order may be granted.If you're going the umbrella insurance route, perhaps see if it will cover you for several things including just the routine slip and fall (like mold or earthquake).

Almost every industry in the world nowadays has experienced massive earthquake of radical changes. 

"and subflooring in the entire house" - Was there an earthquake or something??