When Celeste is spying on Jeffrey and Laurie during their date, she follows them to Jeffrey's apartment. When she gets there, she asks the doorman which apartment Jeffrey lives in, to which the doorman replies, "2D." Later on, as Celeste is leaving Jeffrey's apartment, the number on his door clearly says "2A." They make a big deal about what his apartment number is in the movie, so one would think they'd have paid closer attention to this detail when filming.