Floor Plans on TV:
There's often a floor plan problem on TV shows- there are windows on the interior sets that don't match up to the exteriors shown, that kind of thing.
The Mary Tyler Moore Show is a good example. On the show, every time Mary's front door is open, you can see a stained-glass window in the hallway. There's no such window in that location on the exterior of the house. Also, Rhoda's apartment was frequently referred to as being "upstairs", meaning above Mary's. This was established in the very first episode, and often mentioned thereafter. But when you see Rhoda's apartment, it's obviously a turret room, circular in shape. The real Minneapolis house used for exteriors has a turret, but it's on the same level as the window used for Mary's apartment, not on a higher level.
So, that happens a lot.