I had this issue in a quad and we stubbed each vent out through the roof, pretty simple fix but unfortunately it was too late for the decking which had deteriorated and started sagging thanks to too many years of too much moisture being trapped in there with inadequate venting.

I am adverse to renting it out due to property deterioration and hurricanes. 

Deterioration linked to chlorine water additives has been linked to the failures, however customers on private water supplies have reported many problems.

(2) Impact surfaces are required to be treated only if: (i) Paint on an impact surface is damaged or otherwise deteriorated; (ii) The damaged paint is caused by impact from a related building component (such as a door knob that knocks into a wall, or a door that knocks against its door frame); and (iii) Lead-based paint is known or presumed to be present on the impact surface.(3) Examples of building components that may contain friction or impact surfaces include the following: (i) Window systems; (ii) Doors; (iii) Stair treads and risers; (iv) Baseboards; (v) Drawers and cabinets; and (vi) Porches, decks, interior floors, and any other painted surfaces that are abraded, rubbed, or impacted.(4) Interim control treatments for friction surfaces shall eliminate friction points or treat the friction surface so that paint is not subject to abrasion.

Thanks for your response @Austin Youmans I have confidence that there are no safety or health issues (lol one of our first tasks was bagging the leaves and even some dirt between our house and the little old lady next door due to MOTHBALLS and the awful eye burning smell they put off...it seems she had the notion that mothballs scared off snakes - and since  the property had sat empty for several years there were LOTS of mothballs (both whole and partially deteriorated) - but thankfully they are gone and I would know  - turns out I'm very sensitive  to them.  

Even in gentrifying neighborhoods, you can still have good areas deteriorate if they are outside of where the gentrification is taking place.

The closed auto plants were also often abandoned in a period before strong environmental regulation, causing the sites to become so-called "brownfields," unattractive to potential replacement businesses because of the pollution hang-over from decades of industrial production.[12] The pattern of the deteriorating city by the mid-1960s was visibly associated with the largely departed auto industry.

Generally speaking, does anyone know of a specific example that shows a high scoring elementary / middle / high school neighborhood deteriorate into eventual disaster and lowered home values (perhaps some neighborhoods in Detroit)?

They won't second guess their borrower.The times you will run into issues are with things that can impact the property values....obvious mold issues, structural concerns, deteriorated roofing, potential code issues that are noticed by the appraiser etc.  

They mentioned they don't want to see the house just deteriorate and not sell.