I am really just wondering if it's "socially acceptable" to shoot an email and ask a seller's agent for rent roll numbers on a fully occupied small multifamily.

The reality is, once you get into non-owner-occupied renovation loans and DSCR loans, you are looking at higher rates and/or points. 

Although I’m still looking for properties to owner occupy!

@Alex Hickerson Just to be clear, it sounds like you are not actually interested in buying and holding / occupying the property, but in selling it to someone else that would be able to renovate / add an addition.

I'd go so far as to say this may cause a drop in asset prices, particularly of larger assets which can't be occupied by house hackers. 

Context: Currently, I own an STR and live in it when it is not occupied.

There are also lenders that don't consider how many properties you have, whether the property is vacant/ occupied at purchase and will lend up to 75% (as a seasoned investor). 

Another thing that could be a factor is homestead exemption / owner occupied tax discounts.

How do I account for the rent for the unit that I will occupy?

My original plan was to rent out the property and go do another deal with an owner/occupied low DP loan after about a year.