If so, they are more expensive than a rubber or shingle roofRough Electric- Include fire alarm system on a triplexRough Plumbing- Including gasHVACSprinkler- needed for a triplexDrywallTrimPaintTileKitchensAppliancesPlumbing finishesElectrical finishesFinal Cleaning (negligible in the grand scheme)Landscaping/HardscapingThere are some other smaller pieces that I left out, but these are the majors. 

He spent thousands of dollars and it took him about six-weeks to get it cleaned up.

It’s not just the money but it makes me feel great that I’m also providing other families and their kids with a sparkling clean, beautiful place to stay while on vacation.

If you are going that route, I would definitely recommend expanding your search beyond the solutions mentioned above, both of which are extremely "green" and still building out their capabilities as of 2021. 

It took the PM 3 months to do the repairs/cleaning/market and get a tenant.

David Greene covered the topic on one of the latest podcasts as well confirming that 6 months is a traditional answer for a lot of lenders, but isn't a hard and fast rule, therefore I need to continue to search.Your 75% comment is interesting because many of the HML websites I have been on are all marketing their products around a % of purchase price plus rehab, not starting at 75% of ARV which might (ideally will) cover the entire purchase price. 

Lower Maintenance - downsizing typically reduces the amount of labor required to maintain the home because there is less area available to clean.

He cleaned it up and listed it as 1,900 SF;however, only 925 SF is recognized by the county.

Such as maintaining the garden, cleaning the wood stove, winterizing the windows etc. 

Green roofing?