The reason smaller (2-6 unit) multis are so popular in the Boston area is a) there are a ton of them and b) they are solid, old construction.

East liberty is super popular right now with my generation (young professionals / 25-30s) and garfield is smack in between East Lib, lawrenceville, and bloomfield.

Markups for things like utilities, HOA dues, property taxes, insurance, and even 3rd party contracted maintenance are starting to become way more popular.

Everyone echoing the same popular opinion of "if they are not busy it's a red flag" just to sound credible...

I have a similar experience and my thought is there are probably certain areas where Section 8 is more popular due to rent prices.

There's nothing passive about investing in Real Estate.Contrary to popular opinion on here, I prefer newbies get started with the first method, buying something move in ready in lieu of doing a major value add. 

Gentrification is a MUCH  better solution.Detroit for instance, sometimes $1,500 will get you a SFH that needs big help of TLC.Wait a bit longer and the prices in the neighborhood go up (as the crime recedes).New windows, fixup the porch, some new flooring--and you have a cheap house.Vs. build a affordable/cheap house (prefab or otherwise) and there is no barrier to prevent a neighbor from Section-8ing his SFH and mving in the Crime from the other Cheap areas.At lest with Gentrification, if you get in early enough, you might be able to sell for a big profit if the area becomes popular enough.Detroit for instance as the Detroit Land Bank for hearty (brave) pioneers who wish to live there.Living in any of these fixed up proper homes would be superior to living in a metal container, and most likely based on the price point of Affordability, crime will simply discover your little enclave and move in there the same as the potential gentrified areas.Good Luck!

Normally you get value DIY'ing but ADUs are so popular there's a whole cottage industry right now.

I haven't heard of this company, but the strategy is becoming popular of leasing a property and then subleasing it.

I've noticed that for months now folks are posting about STR questions more than anything else, showing the rise in popularity for newbies to venture into this strategy.