How does that BRRR "Repeat" work exactly?

[Greg Seivert]

I took out a $100,000 heloc on my primary residence (that I am STR house hacking to great success). I used the heloc to buy my second vacation rental, which is also cash flowing after 9 months in. I'm eager to recycle that original heloc and repeat the process! Do I have to wait for the value of my second rental to increase 20% so I have enough equity to cash out refinance and reinvest? At the expense of higher monthly payments and a higher interest rate? Would that be the best strategy? I'd love to hear your thoughts!