PIG-gy backing on Ben Leybovich's unfortunate flooding experience, I wanted to know what methods Puget Sound area investors use to help them evaluate flood risk on a buy-and-hold opportunity.Secondary question would are water-related red-flags for a property, and what are things that give you pause but can be worked with?

Regardless if you buy a house for 1k,  5k,  or 10k once you are done remodeling it, past due taxes,  water bills,  stolen electricity and what ever else might come up you are into these units for roughly 20k.  

Start off feeling the water before jumping in. =).

It has small stuff like water leakage at sink fixture handles, water leakage in sink drain pipe, water stain beneath sink. 

There is a mortgage on the home but it is not under water.

Delinquent Under Water Home Mortgages Declines http://activerain.trulia.com/blogsview/4687562/delinquent-under-water-home-mortgages-declines#.VYGmiEWf9O0.twitter #REALESTATE

The house needs carpet/laminate floors, HVAC Unit heat pump, and minor drywall repairs.  

According to analysis by Ben Leybovich you should calculate about $150 - $170 per unit per month for capital expenditures over time (boilers, water heaters, flooring, roofing, siding, etc, etc) for buy & hold properties.If your $600 is missing some of those items you might be in trouble.Hopefully, you've used the BP analysis tools (free!)

By his own admission, one of his three small commercial properties is still under water.

This necessitates additional (expensive) tear off costs, sistered rafters & all new sheeting.Then there is the possibility that the replacement of the original clay pipe sewer lines will be another unexpected cost along with the need to install sump pumps that must pump to the new french drain you created out back, rather than into the sewer.