Requirements for cash out refinance?

[Christopher Soos]

I am finally taking the plunge into real estate investing. I am going for the BRRRR approach. I will not be able to put down 20% but still qualify for up to a 450k loan (I was slightly modest with my income) I found a duplex with tenants for 350k in a very up and coming area. So after I do some upgrades/updates and the value goes up, how do I refinance and pull out cash for my next investment?