If would suggest finding a contractor familiar with improving the building envelope (air sealing and insulation) for buildings the vintage of yours as applying techniques used for modern construction on older buildings that were not designed to be bottle tight, may require additional measures to avoid inadvertent - and undesirable - outcomes.

If you did pay cash then the question is does the Cash on Cash or whatever metric you use to measure your return align with your goals.

If it's just a rehab and they didn't altered the structural integrity of the building i wouldn't worry; many flippers don't pull permits especially in places like california where the building and safety is something you want to avoid like the plague.

He and his wife are younger and have no kids, so their criteria are more focused on walkability, restaurants, and safety, and less on schools.Does anyone have any suggestions on which neighborhoods to look to for investors or maybe a person they could have coffee with or talk to in the near future?

Once I picked out the slab, they came out and got exact measurements, finalized the pricing, and then had me check the positioning of the pieces from the slab before they cut them.I thought they were pretty easy to deal with, and will definitely use them again. 

Since those are lower interest rates we are considering just saving up for our next property (while keeping a safety net of course) instead of paying down debt. 

When stock picking, would you recommend a search for Value Line's safety and or Morning Star's financial  status to fine tune selections ?? 

Measure roof and figure out size (I’m sure you know) and get quotes again.

Safety issues? 

If you can mitigate the cosmetics and safety items I wouldn’t lose a good deal.