When Nikita & Kelly steal the car, its registration is 20 D 9612. By the time the puncture happens it has become 50 N 9512. Then when Alex and Roan arrive, their van bears the number 20 D 9612.
When Kelly is looking through the binoculars at the border patrol guards she has them held back to front.
While Percy is talking to Amanda we see the back of Percy's head while he's talking. At one point you can clearly see his reflection and his mouth is not moving.
The establishing shot of Eskisehir in Turkey is actually a scene filmed in Berlin and near Alexenderplatz. You can easily spot it by the S-Bahn as well as the German signs for the Bus station and some local shops (like a sign for "Hellweg", a common hardware store in Germany)