Revealing mistake: When Victor is opening the padlock, sparks fly around in close ups. In the wide angle shots there are no sparks at all.
Good Soldier - S2-E9
Revealing mistake: As Michael is on the motorcycle headed toward his loft, just before he goes under the semi-trailer, you can see the long hair of the stuntman on the bike.
Revealing mistake: When Sam pops open the cabinet with the wire he will later cut, you can see that the wire was cut and glued together again. When Sam cuts the wire some time later, it's in perfect condition. The taping was probably done in reverse order.
Do No Harm - S2-E10
Revealing mistake: The drawing little Jack made was reproduced on a printer; it has a perfect 1cm white border around the drawing.
Good Soldier - S2-E9
Revealing mistake: When Michael is sliding under the semi trailer you can see multiple scrape marks going under the trailer. They probably tried to get the shot a few times.
Revealing mistake: Near the end of the episode, when Andy opens the front door to meet Baranski the loan shark, he leaves the door open behind him for the camera man.
Chosen answer: It might not actually have one, in which case, he'd have to go down into the club and use theirs. As for showering, going to his mother's house or a gym membership would take care of that.
Captain Defenestrator