Todd says he is buying his wife a puppy but the dog in the last scene is an adult - not a pup.
When they discover Maria dead on a hillside, Rosemary suggests that she may have been pushed to her death. Maria is on an incline that's less than 40 degrees.
Whilst Rosemary & Laura are driving up hill in jeep to see if they can find natural water source, Mendes is looking through binoculars watching, Rosemarys body double really stands out & is wearing an all turquoise teal top, when they stop at top of hill Rosemary is wearing an orange hoodie over a turquoise teal top.
It seemed like Nicola killed Neil near the end, but then he's there in the garden (after Nicola has been arrested) when Rosemary comes in and they have their moment, and then Laura brings champagne. He could have been a ghost, but no there was no mention of Nicola bashing him on the head.
Nicola didn't kill Neil near the end, he was merely stunned. Nicola ran after he started to speak, which accounts for his appearance in the garden at the end.