Continuity: Bill Murray has fewer balloons when he enters the bank than when he's outside.

Continuity: Geena Davis still looks great even after she has millions of dollars strapped to her person.

Other: At the very end, a plane just sitting at the gate was used to simulate one preparing to leave. The landing gear ground safety pins (with red streamers) were still installed as the engines were started, but the pins have to be removed beforehand to keep personnel clear when the engines are running.

Continuity: When the hostage gives Grimm the watch, a second later he's already wearing it despite never putting it on.