Cash Out Refi on Primary Residence or Rental?

[Jimmy Au]

Hi BP fam!

Let's say you own 2 properties free and clear. One is a primary residence and one is a rental property. Which one is the best to do a cash-out refi on? At this point in time, I only want to refinance one (I enjoy living for free lol). I understand primary residence has better interest rates and I can pull out 80% LTV but is there anything else I need to know? Any tax implications? TYIA!