Hi Sarang,
I also live in NYC part of the year in an older building and I use a subwoofer but I bought my condo on the main floor because I knew there were no basement suites beneath mine.
That said, you'll need to be conscious of deep bass. It tends to go downwards, to the suite beneath you. In any case, consider getting some area rugs, with one placed beneath the M80s. They'll help and also reduce the reverb time, which with bare floors may otherwise be excessive.
My living room is 7 feet shorter than yours; same width, taller ceiling (9.5 ft). I mostly use M22s with the EP500 and QS8s and that setup plays as loud as I ever want it (peaks of 96 to 98 dB SPL C-weighting).
Regards,
Alan
