Other mistake: In the inside of the flat where Jack and Victor dine with Frank McCallum, on the left wall there is a window on the left and a door on the right. However, this is impossible in their block of flats as we see in the exterior shots - there are no balconies and the layout of the building makes it impossible for a door and an exterior window to be on the same wall. From the cast commentary.
Trivia: Just before they started filming series 5, a pest control team had to be called because Jane McCarry, who plays Isa, found a dead rat in the Navid's shop. The rats were eating the food.