They're investing tons of money into those areas, and attracting a lot of good renters who work in the medical profession and will pay good rents to live close to their jobs. 

A study recently completed showed that most squatters are attracted to two properties: vacant and those listed for rent stating 'for immediate occupancy' or vacant. 

Cost of Construction: Since your dad has construction experience and labor connections, the cost of building an ADU would likely be lower than market rates, making it an attractive investment.

Build a system that attracts the right audience.

A combination of extremely tough long term tenant protections and the economics of short term renting being a lot more attractive. 

Quote from @Miguel Del Mazo: Quote from @Jonathan Greene: Quote from @Miguel Del Mazo: We have 3 2/1 condos in our portfolio that attract traveling professionals (medical or otherwise) and a triplex that we essentially BRRR'd down to the studs.

The metro’s unique road system has attracted companies, including Uber, to test new automated car technology, bringing many high-paying jobs to the area.”

A skilled property manager understands tenant segments and their behaviors, which helps attract reliable renters.

It's very unique and I think would be attractive to guests looking for a comfortable get away in the mountains. 

Keep in mind that inexpensive properties are inexpensive because they are less desirable properties in less desirable areas and attract less desirable tenants.