Continuity mistake: In the first closeup of the record player, there are albums behind it. In the next shot, Monica is arranging the crab dip and, in the background, there is nothing behind the record player.
Continuity mistake: As we're watching from outside as Kevin and Lucy talk about how long they've known each other, Lucy's black jacket is off her shoulders. In the subsequent close up, the jacket is fully on.
Continuity mistake: Throughout the movie, the hostess of the party's gloves vary in length. While the one on her left hand stays the same, the one on her right hand is different in nearly every shot we see her in.