First thing is, you are going on the identification of the realtor. Most Copperheads don't get much over 3'. So there is his first likely misidentification. The species is likely another. While Copperheads are found in Orange County, and it is possible, I am skeptical of most "Copperhead" sightings by laymans since 90% are misidentified harmless species.
That being said, I would call an experienced snake removal expert. Perhaps www.snakegetters.com
has someone up there that she knows.