Continuity mistake: When Charlie is with Mia and her father comes in, she's saying: "Daddy, this is Charlie, remember I told you about him." Back when Mia and Charlie were dating, he actually met Mia's parents at least twice.
Continuity mistake: As Alan runs away screaming about betrayal, Berta begins to pour Charlie a cup of coffee. Charlie's first two or three fingers are hooked through the handle of the cup. The shot changes and Berta is still pouring but now Charlie's index finger is alongside the rim of the cup.Guy