Hi y'all good buddies,
Frankly I wouldn't use a CB inside an apartment at all. Even low power (hope you're legal on the 40 channels) can wreak havoc with the signal blasting right across those poorly made electronic toys in the building. Hams have problems like that, CBers are no exception so your best bet is going mobile even if it has two wheels like my first CB mobile. BTW, I was once nearly run down by another CBer in his Cadillac, he's now the president of our local ham radio club and it's a standing joke among the members.