In the second act, Norm takes a break and asks for a coffee or something, and Rebecca calls to Sam to comp him a beer. Sam pours it and sets in front of Norm, who then has a brief interchange with Carla. As the shot returns to Norm, the beer is no longer there and Sam is pouring it again, and then sets it before Norm.
After Norm accidentally paints the door frame then tries to clean it off, streaks of paint appear and disappear between shots.
While talking with Rebecca about painting her office. Norm asks her "semi-gloss or enamel.
These are two things that can't be compared. Enamel is an oil based paint. And semi-gloss is a type of finish.