If the roof is compromised already, you might have rot and mold particularly in places hard to get to.

Has 4 beds, 1.5 bath, basement is clean and dry but not finished.

It targets the babies and dries them up which breaks the life cycle. 

Rotting trim, overgrown yards, etc. 

2nd floor apartment of a 100 year old house, someone decided it was a good idea to pour concrete between all the floor joists, thereby rotting them out.

I'm not investing, retired, but if I were, I would keep my powder dry for now.The other danger is relying on 2 high paying W2 jobs.

Understand dry wall materials etc have gone up because of the trade war.

@Michael Garofalo Unfortunately I'm not the best source of info regarding B-class neighborhoods... as for inventory, I can only relate that in my experience, the MLS seems to have dried up for small multis-- I'm sure they're out there, just not nearly as plentiful as they were last year.  

Buy a clothes rack and let your clothes dry in the sun instead of running the dryer. 

The only thing that comes to mind immediately is "water marks" on the wood hidden behind a wall in the basement which indicate it was previously wet and dried.