Donna's car license plate near the start of the episode was "YD56 VHG". At the end of the episode, the license plate becomes "LN54 VKR".
When Miss Foster uses her sonic device on the window-washer's crane, she points it at the right-side cable, but it's the left-side cable that breaks.
The security guards shoot away the lock on the door, which they then kick down with no real effort. But the door would still be held in place by the hinges - they don't kick it with enough force to rip the hinges out, and even if they had, we can see that there's no damage on the hinge side of the door anyway to demonstrate their forcible removal.
Donna's mother tells her that "no one is unemployed these days". This episode was released during the Great Recession when the UK unemployment rate was skyrocketing...many people were unemployed.