Brrrr Cash Out refinancing confusion

[C-Dell J.]

Hello good people. I'm preparing to purchase another rental property and considering using my HELOC. My plan is to use the BRRRR method. The refinance step is confusing to me. When I google Cash -Out Refi Calculators, I see how to cash out the equity. But BRRRR shows me to cash out 75% of ARV.

Example 1:

house purchase is $100k. Rehab $25k. ARV $175k.

How do I cash out $100k -$125k vs 75% of $50k(the equity)??

Example 2: purchased house over 6 months ago with a loan. Current balance $60k. ARV $83k

How do I cash out 75% of ARV vs 75% of $23k (the equity)??