It was going to go to maxing out the Roth this year, but just sitting there at the moment. 

If I continue to expand into it, I will need to hire an employee (headache of baby sitting) and potentially quit my job

Still better than that $ sitting in the bank.  

I’m 19, and after sitting down and really thinking about what I want to do with my life I decided real estate is the path I want to pursue.

Two den sized rooms would become his/hers walk-in closets, one turned into a master suite nursery or sitting room, and the final one adjoins a tiny bathroom that can be opened up.

Sit on cash during historically low interest rates?

is like to acquire both yet don’t have a lot of money sitting around for a down payment as I just purchased 1 SFH rental.

Reach out to local agents and investors and see who they like to use and why they do or do not like a particular firm, sit down with the attorney and go over the basics make sure you are a good fit.  

If you have two identical 4-plexes sitting next two each other with different rental rates, they are typically going to sell for about the same amount.

My downside on the first option is that I will be running out of cash after a couple houses (with leverage of course) as the money will sit there.