Continuity mistake: The lady asks her for three packs of Chesterfields, at the store, the shopkeeper gives her just one pack, and she can be seen holding and walking with just one pack. When she returns to the house, she puts three packs of Chesterfields on the kitchen counter. (00:24:37 - 00:26:11)
Factual error: The push button phone shown hanging on the wall in Beth's home in multiple scenes was not commonly available until at least the late 1970s if not early 1980s. Push button phones were first available in 1963 but did not look like this and were not in a majority of households until much later.