@Jake Long Congrats on making the decision to start!
I would map out your long term goals first and foremost. Sounds like you want to quit the 9-5 in a reasonable amount of time. If so, unless you're really killing it at your day job, scaling a single family rental business will take some serious time if you're just using your own funds.
I would research the various investment strategies. Brrrr is obviously one of the most common on the forum and would allow you to probably scale faster (again I'm just assuming you'll be saving up for some time for the next down payment). Finding a capital partner and Brrrr'ing could be a way to get to where you want to be faster as well. Also, putting together larger multifamily deals will allow you to use more of OPM to scale.
So start with writing out your goals, find a good agent and get them on the same page if necessary, keep educating yourself, but take action in whatever direction you decide to go!