You could look into different sectors in real estate and see what you like and what you are good at; think 1.

Understand the fees involved and calculate the total cost for an entire year of management so you can compare the different managers.

As far as your primary residence, if you have lived in it 2 out of the last 5 years, you should not have to pay taxes on capital gains (difference between what you paid for it & what you sold it for) up to $250,000 if you file your taxes as an individual and $500,000 if you file jointly with a spouse.Just a disclaimer, I am not a tax professional.

Although whichever option you go with make sure you're also thinking about the long-term property value and what makes the most sense vs trying different angles now that negatively impact future resale/property values down the line. 

I think I was fortunate to find a roll outside of real estate to diversify my income across two different sectors of the economy. 

For example, whole life insurance has at least 5 different terms associated with it now.

There is a difference.$300k cash flow in 20 years is an ambitious but not unrealistic goal. 

Duplex have different zoning that may permit additional units.

If that doesn't bother you, we live in different worlds.

Valuing your time and understanding your limits and skills will make a big difference in the equity you build, the quality of the work and your sanity.