When the kids are at school outside, palm trees are clearly visible. The story takes place in NY. Palm trees would not survive.
There are many inconsistencies with the exterior shots of the home. Some scenes show the side of the house with the enclosed porch. Others show the house with no porch at all.
In the first few minutes of the film, when showing the flashback of the original Amityville murders in 1974, a shot of the Amityville Long Island Rail Road train station is shown. The train seen is a modern model that was only put in service after the year 2000. Also, what looks to be a very tall cell phone tower is clearly visible.