When Max does his Winston Churchill impression for the barmaid, he ends with the famous "V for Victory" gesture. However, he gives it with his palm facing in, which is considered an obscene gesture in the U.K.
The Dutchman keeps referring to Max as 'Herr Scar'. 'Herr' is German, not Dutch. It would be more appropriate for him to say 'Meneer Scar'. this suggests the names of the Scorpion gang don't indicate actual heritage.. the Pennsylvania German Amish are referred to as Pennsylvania Dutch, and speak German. there is likely inaccuracy of El Gato also..
Max says, "Where I come from we always have a little drink to celebrate the closing of a deal." He then gets a wine bottle and tries to smash it, but when he does the bottle is opaque, revealing that it's not a real bottle (so that it doesn't shatter on Max's first try.) In the next shot of it, it is real.
When the Turk opens the windows, a hand can be seen pulling the window open.