Near the beginning, when Alexa is driving Gail's truck with Gail in the passenger seat, and they're celebrating Gail's acceptance into college, the keys can clearly be seen dangling from the ignition in the first long shot of Alexa, but in the following shots from the same perspective, there are no keys in the ignition at all.
When the customer came into the store and bought the set of teeth, his glasses had round dark brown lenses. When Alexa opened the box with the glasses of the latest victim who had been the latest customer at the store, the glasses in the box were the same as the ones he had worn in the store - round dark brown lenses - but when she took them out of the box, they not only weren't round but had clear lenses.