Callie's hair and makeup being neat and perfect is not a mistake, it is quite normal for the family of coma patients to keep up the person's grooming habits.
This episode takes place in Maple Springs, New York, a very small unincorporated town with a population of only 110 as of the 2010 census, yet here it is depicted as a much larger city. It is located in the southwest corner of the state on the shores of Chautauqua Lake in Chautauqua County, yet Sam and Dean are posing as Cumberland County Sheriff's detectives. There is a Cumberland County in several states including: Illinois, Kentucky, Maine, New Jersey, North Carolina, Pennsylvania, Tennessee and Virginia; but there hasn't been a Cumberland County in New York since the 1780's, that county was located in the eastern part of the then New York province and was incorporated into the territory of Vermont when the final borders of New York were established when it was admitted to the union as a state in 1788.
Callie has been in a coma for years but her hair and makeup are perfect.
Sam must have fingers made of steel if he's able to dig a hole in a hard-packed stone road without tools.
At 01:18 -The construction worker refers to himself as: "The wood guy" when, in fact, a professional would refer to himself as a carpenter. Likewise, a carpenter would not refer to lumber as wood.