Walmart offers the Wen 3-Speed Remote Controlled Air Filtration System for $111. Choose in-store pickup to drop it to $91.74. That's the lowest price we could find by $19, outside of the mention below, although it was $4 less in May. It features a 1/6-horsepower motor, filter and pre-filter stages, and timer.

A close price: Amazon charges $93.61 with free shipping.