I might be able to patch in the old wiring in the attached Garage (1/1) and have it rentable; however, the detached garage efficiency has mold damage and most of the wiring had been removed or hacked into.

I am rebuilding a quadplex damaged by Hurricane Matthew and do not have it in my budget to spend 12K on unrentable crawl space.

With rentals people wont care and will damage this. 

Others won't provide a CO with broken windows, interior wall damage, etc.

You could get punitive damages, but this would take completing the lawsuit, which is likely not the highest value use of your time vs other investment activities. 

Something to speak to your adjuster about is whether you have to rebuild/repair the damages or can you collect a check and sell off the property as is to a company that specializes in fire flip projects. 

Paint walls: Does anything need to change about the paint I would use for a flip that has smoke damage vs. not (oil vs. water vs. other)?

In fact, let me preface with a quick list of pro's and cons for a multi-family as compared to a single family.Pros:Proportionally lower taxes/insuranceEase of management(locationwise)Lower roof capital expendituresHigher rent to price ratioRarely fully vacant - can reno-rotate tooLow price volatilityCons:May pay minimum management fees due to lower unit rentsGreater potential for delinquency/damage(Much) higher HVAC capital expendituresLow price appreciationOverall, it's a somewhat bizarre phenomenon to me to watch the money rushing into multis. 

My wife and contractor walked the property to do rehab estimate, found more damage than expected.

Hello, I saw a house in the San Diego area yesterday, it looked like it just needed paint, carpet and updated fixtures from the pictures. 1980 built, but it looked like there is some water damage from a window and I don't know how much I should estimate for a repair.