Continuity mistake: When Sam is in the bathroom holding up two sample paint chips, in the first shot she's holding up the yellow in her left hand and the blue in her right hand, but in the next shot they've switched and are in the opposite hands, just as Jay arrives with the coffee.
Continuity mistake: When Bitsy von Muffling shows up, a man with a white shirt next to Miranda disappears and reappears randomly between shots.