More than one-third (36%) of U.S. house hunters say a “clean” home, i.e. one with high-end filtration systems for air, water, etc., is one of the top three most important features in the next place they live. 

That makes it the most common priority for prospective homebuyers, along with security systems (38% rank that a top-three priority, statistically equal to the 36% for clean homes), out of a list of 22 features.