Ebay offers Bissell air400 Professional Air Purifier for $149 (Reg $399.99) with free shipping.

Product Description:
Clean air made easy. Introducing the BISSELL™ air400. A reliable, holistic approach to indoor air care. Designed for performance from the inside out. Equipped with 3-stages of filtration to capture airborne particles and odors, CirQulate™ System for set it and forget it convenience, and an Air Quality Feedback Indicator that numerically identifies your home’s air quality in real-time. It's clean air you can count on! It also has a large fan and digital 20,000-hour DC motor, that together exchange the air in a 400 sq. ft. room three times per hour when on max mode. Life happens - kids, pets, odors, allergens, dust, and beyond. Let us worry about cleaning the unseen while you rest assured that your family is breathing easy, clean air.

• 3-stages of filtration including a Pre-Filter, an Activated Carbon Filter, and a High Efficiency Filter which can captures 99.7% of microscopic particles on Silent Mode
• 1" thick Activated Carbon Filter engineered to capture household odors
• CirQulate™ System uses a particle sensor to continuously monitor your indoor air and adjust the air400’s speed of air flow accordingly
• Digital Air Quality Display numerically indicates your home’s air quality in real-time
• Automated dimming night mode and Library Quiet operation
• Recommend for medium to large rooms between 300 sq. ft. and 400 sq. ft.
• Included with purchase: 1 air400, 1 High Efficiency + Pre-Filter, and 1 Carbon Filter
• 2-year limited warranty