Normally around 750-600. Airmega is built by Coway which has many reputable air purifier. Camel shows 380s for the lowest price that was back in September 2017.
508.99 + tax was good enough for me to purchase it. Looks like a decent deal if you are in a market for a high end air purifier.
Real-time Air Quality Monitoring
Airmega's air quality sensor tells you the quality of the air in the room in real time. The brightly colored LED ring lets you know if your air is fresh or unhealthy every minute of the day.
Auto: Airmega's Smart Mode automatically adjusts the air filtration speed according to the room's current air quality.
Eco: When the air quality remains good for 10 minutes or more, Airmega conserves energy by shutting down the fan. If the sensor detects pollution in the air, the fan will restart automatically.
Sleep(400S): When set on Smart Mode, Airmega's light sensor detects when it's dark and the air purifier automatically reduces its fan speed so it runs much quieter.