Many so-called "income properties" don't produce nearly the kinds of returns we see advertised on the internet. 

On the other hand, you build wealth by having income producing assets.

for example "the us and Taiwan lead in....." no, it would just be Taiwan, the US produces diddly squat in contrast to Taiwan or, really anywhere for that matter, measuring domestic production vs domestic production.

I don't know.So for $56,000 dollars down plus (an estimated) $7,500 in closing costs plus another $5000 in furnishings, you get an asset that produces about $500 dollars a month. $68,500 / $500 per month = about 12.4 years to get back the intial investment.  

So while they take their management fees, their incentive to produce is nowhere near what I would like. 

It is possible to achieve better returns, but this property has already produced outstanding return and requires little effort for this return.Good luck

The articles conclusions MAY be self serving - we need to look closely  to perceive any motivations for WHY the writer is producing the article. 

I'm reading another experts book and they talk about how Triple Net leases aren't really the greatest to produce income, and in one of Peters videos I just watched he says investors LOVE triplenet leases.

One portfolio gives me cash flow and debt pay down, while the other produces appreciation in addition to the other benefits.  

Theoretically, I would guess an ADU adds value to the property because there is an additional income producing unit.