Another idea I had was to just use standard research out there on building systems like the air conditioning, wiring, plumbing and so on, to estimate how much time they would normally take to require repairs.Here's a paper that discusses "energy modeling" for single family homes that is pretty recent that is an example of what I'm thinking of:https://www.mdpi.com/1996-1073/12/8/1537 

@Drew Harris   I've used Demetrius Crowder several times for plumbing work. 

-reliable "handyman" who can deal with minor repairs (make sure licensed and insured)-tenant self-inspection app or use third party service for inspections-vendors to service home functions, e.g. plumbing, electrical, HVAC, etc.

Things that drive the ARV the most - roof, plumbing, flooring, paintThings that don’t drive ARV as much - windows, landscaping, driveway

@Austin JamesUnderstand the area, the current tenant base,the median income, is it in a flood zone, the age of the asset, the condition of the plumbing, the electrical wiring, the fuseboxes, the age of the roofs, the age of the mechanicals, the condition of the foundation, the drainage of the property, does the property have a C of O, is there ny environmental concerns such as oil tanks being buried, the current property management company, what are the amenities.These are just a few things to look out for.

Now let's look at the before-and-after cost segregation results:- moldings went down from $17k to $4k- $20k security system disappeared altogether- specialty plumbing dropped from $19k to $11kand you can review the rest of this side-by-side comparison yourself.Unlike my restaurant analogy, reduced or eliminated numbers on cost segregation are not only suspicious but they are outright detrimental to the investor.

Usually if there is a plumbing or electric issue, it falls on the tenants.  

Properties that were converted a long time ago, or likely converted without permits, and not to today's building regulations.Not knowing how the property was separated by its units means that you don't know where the electrical, plumbing, or other mechanicals run.

Some things to consider are the age and condition of major systems like the roof, HVAC, and plumbing.

., plumbing, electrical, roofing) and try and estimate the costs for each.