Multi-Family House Hack Investment - 50/50- How to Structure?

[Stephen Massinello]

Hi BP, I am looking to go in 50/50 with a partner in a multifamily house hack. He will live in one of the two apartments in the Multi-Family. 

Assuming down payment is 50/50, how do you then structure who pays what? all costs 50/50?

Let's say there is a 2 bed and 3 bed and he stays in the 3 bed? 

As I am writing this, it makes sense to me that it would be 5050 cost down the middle after the rent from the 2 bed is subtracted out of the total monthly expenses. 

If anyone has a document or any tips on this type of deal, please let me know. 

Thanks