Around the 54th minute, Raymond rises from his bed and puts on a solid-colored robe over his pajamas. The next shot has Raymond descending the staircase, and he is now wearing a hounds-tooth coat instead of the robe. Raymond turns a corner and enters the kitchen, and he is no longer wearing the coat and is instead back to wearing the robe.
When Gary Merrill's partner in murder rolls the car over the cliff containing the body of the actress impersonating Merrill's wife the Triumph TR4 they arrived in turns into a 4 door sedan at the bottom of the cliff.
At 1 hour 13 when the outside of the house is shown at night the sound of crickets is played over the shots. This is not an thing which happens in the UK.
When Raymond puts Ellen on the bed after killing her in the bathroom, you can clearly see she is still breathing.