Continuity mistake: Bernie gets shot underwater with the spear and can't let go of the chest. But when they take the vest off Larry to float Bernie up to the surface, Bernie takes his hand off of the handle to get the vest on.
Revealing mistake: When Bernie gets shot underwater after the kids remove the treasure chest, they carry Bernie. He's dead, yet you see his head move.
Plot hole: In Weekend at Bernie's one, Larry takes Bernie's watch and never puts it back on the body. In Weekend at Bernie's II, he gets the watch at the morgue after it's been taken off the body, and signs for it. How did the watch get back on the body?
Visible crew/equipment: When Henry and Charles are released from prison after the subway fight they are walking across the street discussing their next plan and then stop on the side walk. In the background you can see a woman with a radio redirecting pedestrian traffic on the sidewalk away from the movie set. A few men stand around asking her questions and watching the actors. (00:47:53 - 00:48:43)
