How did you finance your second rental?

Hi all! I recently joined BP and this is my first post. My wife and I are super excited to get going on our REI journey!

Our plan and motivation is nothing new. We want to primarily buy and hold rental property to replace the income from my current job so I can quit and spend more time with the family. We just had a baby on Christmas so my perspective on the value of free time has completely changed.

Anyway, we've been very fortunate and actually have enough money to put 20% down on something toward the lower end in our market even though it's incredibly hot. But, how do we keep going from there? I hear all these stories of people getting into real estate and buying half a dozen properties in a year and I just don't understand how to get there. We just attended a webinar put on by Brandon Turner and he said his minimum cash flow on a SFR would be $200 per month (which we'll need to be creative to get). But it would take years to save up enough for another down payment just from that cash flow.

My current job pays well so I won't be quitting anytime soon, I just thought buy and hold would snowball quite a bit faster than this. I've toyed with getting a real estate license and acting as a real estate agent on nights and weekends putting the commission toward more properties. But with the end goal being more free time, that's a bit hard to swallow. For those with multiple rental properties, how did you scale up in a reasonable amount of time?

Adam