When the tape is played in Flora Carr's office, Norman turns on the playback switch and the tape is running in fast-forward. In the next shot it is turning normally.
When Norman opens the door during a rainstorm, the rain is seen to be coming from a sprayer (unseen) in a widening pattern. Rain doesn't fall this way.
Tansy says that one of the firemen said the cause of the fire was an oil stove. It would be impossible for the cause of a house fire to be determined while the fire was still taking burning.
Tansy awakes to the house being on fire in flimsy negligee bed clothes. Yet when she reunites with Norman outside she has changed into wearing normal day clothes.
At 1:21:48, you can see the guide wire controlling the eagle.stretching from it's leg to it's handler whose back is briefly seen.