Tracy Richards' penthouse suite is the same set used for the Manhattan apartment of Oliver and Lisa Douglas on Green Acres. Both of these programs were created by Paul Henning.
When Tracy Richards and her secretary are looking through the Clampett Mansion looking for changes she wants made- she asks for the name of an Italian designer. Doug's response "Scarpitta" - this was a nod to show director Guy Scarpitta, who's father was a sculptor.