I used HELOCs, 1031 Exchanges, and partnerships to expand the portfolio.

A mixed-use building with an Urban Mix zoning is not easily summarized.

Here is the current list of cities:http://ritaohio.com/MunicipalitiesI am rather sure that the list has only been expanding over time.As a person/entity who earns rental income in any of these jurisdictions, you are required to file a return not only for the state, but also for RITA.

We were looking at buildings in Berwyn here in the Chicago suburbs for 220k that are now worth 450k easily. 

If you were to venture into STR I would suggest starting with one to test the market and see if it is something you would like to continue to expand into. 

Is there a reason why someone who could easily afford a VA would rather pick JV partners instead?

Quote from @Sherica Chambers: Hi Geoffrey,I recently expanded into the Ohio market and am actively marketing to sellers in the area.

If they are professional, they can explain this quickly and easily.

Also, what can be rented out easily, in terms of size and number of bedrooms?

You can join local real estate investment clubs or online forums to expand your network.Start small: Since you're new to real estate investing, it's a good idea to start with smaller properties under $400K.