ecobee4 Smart Thermostat w/ Sensor – Costco by Rhonda March 12, 2023 *UPDATE* 12/17/19. Select Costco locations have the ecobee4 Smart Thermostat with Room Sensor on sale for $149.99 (after instant savings), now through December 24, 2019. That is $50 off Costco’s regular price… 0 FacebookTwitterPinterestEmail