I would want to make improvements to all units and increase the rent to market value when the renovations are completed.

Challenges?

This upgrade not only improved comfort but also significantly modernized the property.

She paid us up front for 12 months of rent & then paid herself each month & at the end of year 1 she paid us for another 12 months...she did this until her credit improved. 

See the chart from Fair Isaac Company (FICO) below: FICO Score Pct of Population Default Probability 800 or more 13.00% 1.00% 750-799 27.00% 1.00% 700-749 18.00% 4.40% 650-699 15.00% 8.90% 600-649 12.00% 15.80% 550-599 8.00% 22.50% 500-549 5.00% 28.40% Less than 499 2.00% 41.00% Source: Fair Isaac CompanyAccording to this chart, investors should use corresponding vacancy+tenant-nonperformance factors of approximately 5% for Class A rentals, 10% for Class B and 20% for Class C.To address Class C payment challenges, many industry "experts" are now selling programs to newbie investors about how Section 8 tenants are the cure.

. • Documentaries: Check out The Queen of Versailles for insights into the challenges of hotel investments. • Podcasts: The BiggerPockets Commercial Real Estate Podcast has episodes on niche asset classes, including hotels. 

Living with your tenants can be very challenging speaking from experience. 

If you’re looking at retrofitting to separate heating for each unit (like furnaces or mini-splits), you might be looking at a higher upfront cost, but it can shift utility expenses to tenants and improve your NOI.I’d factor in boiler age and efficiency when analyzing deals and if it’s near the end of its life, negotiate a price reduction or a credit.

I did minor improvements to both of those, but unfortunately had to replace the roof on each (Flat roofs suck, lesson learned).

.: @Don Konipol Hi Don, At the point where I am in my business, I am thinking (a lot) about improving and growing my business and profits.