Here's what the house really looks like... (Gotta Love Dare Counties Website)
It is owned by a couple from PA. Looks like they "cleaned it up" for the movie as the house in the trailer looks a lot better.
This house is the first house on the left when you enter Mirlo Beach which is the start of Rodanthe.
From what I heard they filmed some of the movie here but a good deal of the movie was filmed on Topsail Island also.
Most of the parts filmed here were filmed in the middle of a Nor'Easter.
Matt