Coway via Amazon has Coway Airmega 400 Smart Air Purifier on sale.
Price is $365.50 with Free Shipping.
Also Walmart has Coway Airmega 400 Graphite Smart Air Purifier for $365.50 + Free Shipping.
Smart Note: This offer is valid until Saturday, Sep 7, 2019 or anytime before that. Check the price before you make a purchase.