Also, if a feature is trendy enough for long enough, it starts becoming a pretty safe bet.

I'd also love to see some analysis on feature correlation. Is a central vac actually something that people pay more for, or is it something that is frequently noted in listings and correlates with features people do pay more for?

Yeah this was the first question I had! I mean if 100% of homes with heated floors also have tankless water heaters, the floors might actually account for 95% of the boost that's attributed to tankless heaters.

Or is it merely that central vac is highly correlated with square footage and neighborhood age, each of which might better predict prices.