Other mistake: After taking a knife to the leg, Starsky hops off in obvious pain, not able to put weight on the hurt leg. When he is putting his "bad cop" routine on for the Korean man, he walks perfectly fine, but then when he walks from the door to the table (after Hutch and the man have their meal and conversation), he walks with a very pronounced limp. (00:56:25)
Other mistake: When Starsky and Hutch arrive at the Bar Mitzvah there is a jazz band playing. Look carefully at the bass player, he's not playing the bass at all. His hands don't move every time he plays another note. (00:59:45)
Other mistake: There are two different yachts in the boat scene in the end. One is driving away when the car has sunk, next boat is when you hear the horn and the zoom in on the boat again. The have the same name (Oasis), but the opening in the stern/steering wheel are in different places and the name differs. (01:29:15 - 01:29:50)
Answer: It's entirely possible, since they were not wearing their disguises at the prison, that they had already changed clothes, and therefore, could change vehicles.
Phoenix