Student loans vs saving

[Samuel Pascal]

Hey BP family. I am currently in a situation where I need to make a decision. I graduated college with 42 k of debt and brought that down to 17 k by aggressively paying monthly, refinanced to 4% int, and getting a new job. My DTI is 32% and credit score is 748 monthly debt payment is 128 now. I make 54k in NYC and currently living with parents ( basic millennial) but I'm taking advantage of a deal with my father to pay off debt instead of rent. Given this, I'm looking for your opinion. Should I pay off the 17 k aggressively or save up money for a multifamily using brrrr strategy. Looking at Yonkers NY or Jersey since NYC is impossible.