So Long, Frank Lloyd Wrong - S7-E7
Continuity mistake: When Joe and Helen are talking to Y.M. Berg, there is someone at the AeroMass counter that is seen leaving twice.

So Long, Frank Lloyd Wrong - S7-E7
Continuity mistake: When Joe and Helen are talking to Y.M. Berg, there is someone at the AeroMass counter that is seen leaving twice.
Visible crew/equipment: When Nina hands Casey her glass, a boom mic is visible.
Return to Nantucket: Part 2 - S1-E4
Revealing mistake: Carol closes her eyes before Helen throws the pie in her face. There was no way she could have known it was coming because Helen was hiding the pie.
Joe Hackett: This is the dumbest thing Brian's ever done, and he once painted me blue.
Joe: If ifs and buts were candy and nuts, we'd all have a wonderful Christmas.
Roy Biggins: If you'll excuse me, I've got to get ready for the big night.
Alex: Oh, that's right, you're about to romance a woman. You'll want to shower, shave, buy chloroform.