Deliberate mistake: At the end fight scene, when they are in the barn one of the men falls crashes through the wall when they get hit, spilling the fight to the outside. Unless the barn's walls were made of cheap plywood, the wall would not have given away so easily. Obviously done for dramatic purposes.
Deliberate mistake: In a couple of scenes, Bandit's Trans Am's engine sounds are dubbed, and you can hear the shifting of a manual transmission when his car was an automatic.
Deliberate mistake: The 27th floor is very tiny indeed, despite the outside view showing it to be as big as any other floor. On one end is the stairway. On the opposite side is the elevator Adam's team rides up in. There are only 4 rooms total, and between two of the room doors is the elevator ridden by the security guards. Also, logistically, the security Guard's elevator cannot be there if you notice the area at ground level where Adam's team enters their elevator. (01:46:40)
Deliberate mistake: The floating candy bar that clears everyone from the swimming pool is a Baby Ruth, but Baby Ruths don't float, they sink like a rock.