Dark Tourism is a huge thing. So-called "murder houses" tend to get curiosity seekers. There are some people who literally travel all over the world to visit places where crimes, murders, and the macabre have happened. My family in Delphi, IN constantly complain about the influx of travelers from other states-people who take selfies in front of the victims' houses. If the Watts' house went on the market, I have no doubt it would generate a lot of interest, both from curiosity seekers and from legit buyers who aren't uncomfortable with such histories. It's even possible that it would sell to someone who wanted it BECAUSE of its history. The Visillica Ax Murder House charges people to spend the night in sleeping bags. Of course, it is reportedly haunted, but some people travel to it simply because the whole family was murdered inside.