According to Megan Mullally, the cast was given free access to improvise as much as they wanted to and eventually 240 hours of films was shot on camera, which had to be trimmed to 90 minutes for the final film.
Many of the paintings in Laird's house were actually by James Franco himself. The movie's closing credits acknowledge that. Franco is an avid painter and his artwork is featured in many of his films.
The bedroom scene between Megan Mullally and Bryan Cranston was not in the original script, but suggested by Mullally during rehearsals.
This script was originally entitled Aloha, with Ben Stiller as the father and Jonah Hill as the boyfriend, and was set in Hawaii.