The building would ideally consist of apartments on the second and third floor with commercial space(s) on the first. 

Since you are renting an apartment for $900, realistically you are paying out of pocket $650 to live under a roof.

For multifamily/apartment education, check out Best Ever Apartment Syndication Book by Joe Fairless!

This might still be a lot for applicants in a C-class neighborhood, but it will be much less work for both of you if they can do it online (again, assuming they have access to a computer and a debit or credit card).

You are smart for not getting suckered into courses that offer little or no insight apart from the usual marketing platitudes. 

Raising/Saving capital is a part of that.

(Furnished is also less wear and tear on your walls).Post on Airbnb ASAP your furnished rentals and offer by the bedroom and by the apartment starting immediately while you are leasing up.

For my first investment, I am pursuing apartment buildings for passive income.  

I try to be a part of big enterprises that can also withstand movements in demand and that are affected by national and international relationships, subject to competition, and are a part of world markets.

Plenty of duplexes, and plenty of 4 unit apartment but never 2 duplexes on the same property with such a large living area.