Continuity mistake: When we see Elmer pressing the bell at the start of the cartoon, there is a book by the bell on the reception desk. When Elmer tells Daffy to take the businessman to Suite 666, the book has gone.
Continuity mistake: When Daffy finds the key to Suite 666, the shape of the keyhole is that of a normal key. In the next shot, it is round.
Continuity mistake: When Daffy comes up the stairs laughing and enters the businessman's suite, the number of 666 on the door is different to that when Daffy and the businessman arrived at the suite earlier in the cartoon.