A lot of handy persons are very poor at troubleshooting and just take the easy way out too.

If she had told me earlier, I would have trouble shooted the problem earlier.Is there more for me to do?

PM spent multiple days troubleshooting issue and ultimately we had to replace projector under warranty.

What you and Phil want is The Rust Belt Troubleshooting and Maintenance Guide to Aging Residential Property, free e-Book edition, with Property Snagging Checklists and Additional Forms. 

before sending out a service tech (I'd remind them that last time there was no trouble found and threaten to charge them if they balk at appropriate trouble shooting).

I really like Millionaire Real Estate Investor by Gary Keller, more of a general REI book and Hold, mentioned above by Gary's company also, Hold is a lot more buy and hold focused and has a lot of good and practical info like the property evaluation sheet.Another book I am in the process of reading and have heard a lot of good things is Landloridng on Autopilot by Mike Butler.Landlording is also a must have book for anyone that manages properties.Landlords Troubleshooter is also very good to read.The Landlords Kit by Jeffrey Taylor is also a great book for forms and processes.

In a 300 unit apt community, I can hire a FT handyman that can go purchase 300 toilet handles (should be able to negotiate cheaper price per handle than w/SFR where I have to pay retail), the handyman is not charging me a per visit call and will know exactly why these flushers fail while an outside person at your SFR may fumble around, troubleshoot and not fix it right since its the first time visit to your property.But the other one is that commercial real estate is valued differently than SFRs and small MF (4 units and under) which are valued by comparables to other like properties.  

You MUST source people that are excellent at troubleshooting issues, project management, and that understand the importance of quality repairs.

Financials, before/after repair pics and reports, annual inspection reports, and perhaps most importantly, typical repair costs...water heater replacement, toilet replacement, faucet replacement, yard service/snow removal costs, window/screen repairs, electrical troubleshooting calls, HVAC services, etc.

They’re great for mitigating shade and come with individual panel monitoring so you can see individual panel production, track degradation more accurately, trouble shoot easier if necessary etc.