I despise units that are older where sound travels easily or also units that have either more units above and below.

Others do this at a much higher level.

I live on the main unit. 

Units are cheap and they just put a Starbucks in so there's got to be something growing there.North of Worcester ie. 

I know that my current cash flow is a result of the unit being my primary residence first, and that not all units will cash flow like this, but can't help the feeling that I should be expanding my rental portfolio over the years.

You can 100% use an FHA-203k renovation loan on multi-unit properties up to 4 units. 

I have a complex next to mine that has over a hundred units, some do very well some dont and you can point to their decor right away as a differentiator.

We have pulled permit for one STR, like air B n B and have furnished one of the units.

My experience with the smaller multi-family units has been that more occupants = more wear and tear on your property so the turnover costs are often higher than SFH.

I am considering living in one of the units myself.