My husband did 90% of the work himself, only using contractors for large electrical, plumbing, and construction projects.

Roads, water, sewer, gas, electric, etc..I'm also here for any discussion on any other items that might be of note, trying to learn as much as possible on this front.

The limit on scaling is your deal flow (mine never was that good) and time it takes to perform the value add (I got fairly quick for example, my last rehab did all new plumbing, electrical, and flooring.  

@Alecia Loveless is correct--tenants need access 24/7 to their electric service panel, water and heat, assuming those are individual utilities for each unit. 

The company managing our property as a vacation rental was unable to get the power turned on in our condo for months because we had to get the meter switched into our name with the electric company (which is much more difficult to do in CR than in the United States).

Also, how much did the electric and plumbing fixes costs?

., major systems like plumbing/electrical)Full Gut/Studs Down: $85-$120 per sq. ft.Luxury Finishes: $150+ per sq. ft.For ARV (After Repair Value), you’re absolutely right—it’s all about comparable sales ("comps").

Additional Info —Key Details:Location: Outside Santa Fe, NMProperty Size: 20 acres (valued at $80,000)Project: Two new STR unitsExisting Experience: Family has two fully-occupied LTRs nearby, generating $2,000/monthConstruction Approach: Self-contracted with licensed trades for electrical/plumbingCost Assumption: $80,000 per unit, plus ~20% for inflation (based on 5–8-year-old build costs)Financing: Using land equity as down payment on construction loan (expecting closing costs to be major expense)Request: Looking for feedback, potential pitfalls, and general guidance

I would be more hesitant if they were added on (new plumbing and electrical) vs just upgrades to existing.

Avoid any self-help eviction tactics like changing locks.Maintenance: As a landlord, you’re responsible for ensuring the property meets basic health and safety standards, including working plumbing, heating, and electrical systems.Inspections: While there are no mandatory inspections required before renting, your property should comply with building codes.