as he does for buyers who want spirits to skedaddle, mark implores any perturbed paranormals in thisa fixer-upper elsewhere. >> i'm asking all negative energy to leave this room. >> we're gentle in our approach. >> reporter: but you're evicting these spirits. >> we're not evicting them. we're helping them. >> reporter: what happens when somebody gets kind of a gleam in their eye when you tell them that the house they're looking at is haunted, that they're excited at the prospect? what's that like? >> well, i usually call a security guard to protect me because they're usually nuts. >> reporter: in cali and elsewhere, realtors are required to tell buyers if a home purportedly has ghostly inhabitants. landlords? not so much. this week catrina mcghaw told kmov in st. louis that she learned from a tv documentary the apartment she'd rented had been used by serial killer maury travis. >> this whole basement was basically his torture chamber. >> reporter: why hadn't she been told? maybe because the landlord was the serial killer's mother? haunted houses can come in all shapes, sizes and scar