air & water via eBay offers the NewAir Portable Evaporative Cooler With Built-In Air Purifier, model no. AF-351, for $149.95 with free shipping. That's the lowest total price we could find by $50. It cools up to 300 square feet and features a 1,000 CFM air flow, 5.3-gallon water tank, three fan speeds, and 10-hour timer.