Continuity mistake: When Mother and Mameha are waiting for the bid on Sayuri's mizuage, Mother's cigarette is short at one point, but becomes longer in the next shot.
Factual error: The troop trucks you see belonging to the Japanese Army are incorrect post-War models. During World War II, the Imperial Japanese Army employed trucks that were nearly carbon copies of the Studebaker 3-axle 2 1/2 ton model (or used captured British Bedford trucks).
Plot hole: When Pumpkin is telling Sayuri about Hatsumomo talking to Dr. Crab, she says that she was waiting outside during the conversation, and while she could hear it, she couldn't see them. However, at one point Pumpkin describes a facial expression of Dr. Crab.