The glass panes above the external office doors are opaque and curved when viewed from the inside, but in exterior shots, the glass panes above the office doors are transparent and rectangular.
Once during the show's first season, Martin states that the Kellys' street address is 33 Jacaranda Avenue; in the series finale, Greg mentions that the address is 26 Jacaranda Avenue.
When Rachael Beck debuts in season five as Sam, Martin recognizes her as the daughter of his older brother Mark. In season one, Martin had reminded his mother that he was an only child and did not have a brother.
Despite the fact that non-reflective spectacles were specially made for Robert Hughes, studio lights are often visible in their reflection every time he looks upward in close-ups.
From episode 20 onward, Betty often displays an inability to correctly pronounce the words "architect" and "secretary", after having had no prior difficulty saying these words properly.