Continuity mistake: In the scene where Dick Shawn and all the characters find the box of money under the big W, Shawn has just thrown Jonathan Winters out of the hole so he would have room to work. But in the next five edits, Winters is both in the hole helping Shawn struggle with the box and is also shown standing outside the hole observing himself along with the others.
Continuity mistake: In the last scene when they are all on the fire escape, there is one part where the landing nearly collapses and Sylvester is seen nearly flying off the landing. The next immediate shot shows Sylvester fighting for the ladder. He apparently climbed up the landing and crawled over a bunch of people in a fraction of a second.