This air purifier is expensive but, oh so worth the price. I had this in my nail salon until I had to sell my buisness due to my moms illness. I sold theHoneywell with my buisness. The buyer could not believe that I used it for the strong smelling nail enhancments. I didn't even tell them that I allowed smoking. This is a great "industrial" air cleaner. My Honywell air cleaner ran on medium speed continuosly for 11 months. Only had to change the hepa filter once and the pre-filter twice. The pre-filter collected the dust that was created from filing artificial nails. My non-smoking clients didn't even know that my smoking clients smoked in my 900 sq. ft salon! About once a week you can turn it on high to really give the room a good cleaning. This air purifier can be used in a home, although it is noisier that the more compact ones. The Honeywell brand is the only brand that I will buy. I have the smaller one in my home, which I will review as well. A great way to delay purchasing the pricey hepa filter is to keep the pre-filter clean. I take it out, lay it flat and use my sweeper on it.