I have a very flexible job schedule, I don't know how one would do it otherwise. If I need to be out of the office a few hours I can make it up in the evening as needed. Most of that flexibility I have earned over the years and I'm not in a "customer facing" position.
There will be some sacrifices in "free-time", there is no doubt about it. The amount varies in how dirty you want to get with your hands in your projects. Your "team" is critical - buyers agent, financing, reliable contractor or subs if you manage the projects, etc. Do things in a process that can be repeated every time- property types/location, paint colors, rent listing templates, application and rental process, on and on.
Now with a family, full-time job, and REI it makes me wonder what I did with all my time years ago ha! But, I enjoy it or I'd stop doing it tomorrow. You have to find your "why" early on and keep it in mind.
I'd recommend selling your TV set. You won't have time for that anymore :) Look for the book recommendations sprinkled through this website or on the podcasts. Brandon's book you are reading now is a great start.
Most importantly enjoy your journey!