My sister works in real estate, and she was asked by a Realtor she works with what the law was on disclosure for a house the seller said was haunted. In most US states, it's legally required to disclose any material fact about known issues with the property, though how it's worded and what that includes varies from state to state. She had to look it up, and in North Carolina, haunted is not a required disclosure, though it is in some states. I joked that haunting should count as an "immaterial" fact.
She was laughing about the whole thing until she went by the house herself to make sure everything was ready for the photographer. She heard a noise in the basement and checked. There was an old black man dusting the shelves. She mentioned she wasn't expecting anyone to be there. He was very polite and explained that he took care of the house, and not to worry, he'd stay out of the way. She went upstairs to let in the photographer. When she went back in the basement there was no sign of the man, even though the only way out was past her. She looked around the whole house for him before she locked up but he was gone. She asked the seller about it, who casually explained that that was just old Terrence, who had taken care of the property for her grandmother, and had died many years ago. Since then, he just sort of appeared around the house occasionally, "tidying up." (I'm writing this from memory, so some details are probably wrong, especially the name, but it's the gist of story as she told it.)
They did not mention any of this to the buyer, and don't know if they ever experienced anything as they never contacted them about it.
