Costco offered Solar Powered Attic Fan Professional Series at $299.99. On 2013-12-16, Costco reduced price by $20 from previous $319.99. It's the best offer since 2013-12-16. The biggest price drop was $80 on 2012-06-09, offered at $319.99, which was higher than today's price. This offer might be expired. The last price tracking was done on 2013-12-16.