A good question. Wow, why didn't I go ahead and put more details in about the building itself? Odd. Like, the biggest part of the RP has been left as a blank canvas. I am not smart. 

But let's correct that, shall we? 

Being a British man of great esteem, who lives in a flat himself, I'd say that the stairs are at opposite ends of the floor. I've been in many such structures, and they've all been designed along those lines - though not to say that all "apartment buildings" in England are like that.

HOWEVER, as I set this RP in America, I'll ask the question to my colonial brothers. 

What's the standard set up in America? Or isn't there one? 

A google image search is showing me stuff like this:

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[img]http://www.herald-examiner-los-angeles-filming-location.com/wp-content/uploads/2013/03/Apartment-Stairwell-Los-Angeles-Filming-Location-Herald-Examiner.jpg[/img][/hider]