At the end of the movie when they are being chased by the evil spirit, the two people run up one flight of stairs into the attic, when obviously they had been on the first floor. Where are the other floors shown in all of the outside shots?
Most of the other floors featured on the outside of the house are actually the basement, the only reason it looks like a skyscraper is because it is mostly buried in a hill. Another explanation is that when they enter the house, the main door is at the top of the hill, leaving only about 3 levels above the crest of the cliff side, and the rest below.