i would not tell your superintendent or landlord
unless A) they live near and might hear you or B) you are close and they are cool w/ it, in which case they probably already know
they might take it upon themselves to tell you that you can't do that if they are a homebirth skeptic and you absolutely CAN
you do have a right to privacy
you might tell people in earshot, upstairs downstairs neighbors, if you share a wall w/ somebody
but i would even tell them, if anything, that you are planning to labor at home and if you get a little noisy, that's what it is and it's ok
i've had 3 births, 2 different apts and a duplex
and nobody ever heard a thing
it is scary to think of worst-case scenarios like somebody hearing noise and thinking you are being beaten to death and calling the police or something
but i think it is probably MORE likely that you tell somebody ahead of time, they don't understand homebirth and they give you crap about it
kwim??
so i don't know, i think you have to feel it out in each situation
i would be scared tho' to tell my landlord ahead of time (i never have)
afraid they would try to say i can't and it would be a stupid hassle
assuming that anybody who would hear you knows already that you are pregnant, if you leave a note i might say something like
"thanks for your concern, everything is fine"
or "please respect our privacy"