In Hawaii we do not have to disclose ghosts.  It is a specific exclusion in our real estate law.  I still recommend my clients disclose them, because it is a material fact, that may effect someone's decision to buy.

There is a famous real estate ghost story in Hawaii.  There is a corner home on Harding Ave. that is considered the most haunted house in the state.  It was part of the ghost tours, etc.  The owners tried to sell the home a couple of years back and the reputation made it impossible.

Their attorney, who also teaches GRI classes, researched the history.  They found out that the home was the site of a radio show Halloween prank many years ago.  The haunted part was a complete hoax.  Over the years the story took on a life of it's own.  To this day, I know people who refuse to even drive down the street.