During production, Richard Donner was shocked when Mel Gibson confided that he was drinking five pints of beer for breakfast. Despite his alcohol problems, Gibson was known for his professionalism and punctuality.
The scene where Mel Gibson attaches cables to the stilts of a mountain-top house and pulls it down cost over $500,000.
Leo's "okay-okay-okay" schtick was based on Disneyland employees giving directions to guests at Fantasyland. Originally, Leo was going to be an oily, effeminate character, but Joe Pesci didn't want to play him that way. He pitched the idea of making Leo all-too-eager to please, complete with "okay-okay-okay" ad libs, to Richard Donner. Donner laughed and said, "Do that! Do that!" The phrase is referred to in Home Alone (1990) by having the phrase "Oh, K Plumbing" painted on a van driven by Joe Pesci's character.
On the side of Riggs's refrigerator is a U.S. Army Military Police School diploma.
During the scene where Martin Riggs is talking about his gold pen, and is making what is presumably a pot of chili, he can be seen crushing Oreo cookies into the pot. Later in the movie, Riggs asks Rika if she likes her chili "with or without crushed Oreos".