I currently have a small portfolio but they are single family homes. 

I guess it always seems like they don't want to make low offers on my behalf or after you walk a few homes that don't work out they check out. 🤷  

Begin with small, easy-to-manage homes like single ones or two-family homes, or try house hacking to help pay your mortgage.

I don't own my own home, so even the home buying process is new to me.

The home has a basement, which, with some work, can be a 2 bedroom one bathroom unit.

learned a lot about construction and improving my efficiency and knowledge.

Generally speaking, we would encourage you to screen your tenants - whether they are section 8 or not.We would encourage you to collect a deposit - whether they are section 8 or not.A tenant can certainly be a "good" tenant or a "bad" tenant - whether they are section 8 or not.Now, if you are targeting lower valued homes...there are "pros" and "cons" to doing that - whether you are renting to section 8 or not.  

Anyway, code enforcement asked to see the inside of the apartment & i agreed as i was doing some improvements inside like painting etc.....afterwards he nailed a red tag to my wall which i didnt pay much attention to because I was literally unaware of what it was or what it meant.

OR could you buy multiple SFH homes rather than duplexes?

So a modular home fully built in china and shipped here will be out of question.