Cashout refinance for triplex building

[Ramel Ruffin]

Hello I am looking to purchase a fully occupied triplex apartment building. I was wondering with the building fully occupied is that already considered equity in the property so for example 3 units pay 1,000 for each unit grossing 3,000 a month (36,000) a year would that be already 36,000 in equity? And if so would I be able to do a Cashout refinance like people do with the BRRRR Strategy?
thanks in advance