Owner occupied with partners

[Nicole Lindgren]

Hoping for some advice on the following scenario: Couple A and couple B just started investing. They have one rental so far. There is a home available that could be split into 2 units with a 3rd one over garage that needs to be rehabbed significantly. Couple A is willing to live in the bottom portion in order to get the better rate and less down since it will be owner occupied. They are willing to pay rent as well. How would you work it to make it fair for both parties? Is this a good/bad idea?