Three Roombas on sale currently. 3C has shown significant price differences even within past week. Prices are relatively similar to pre-Christmas 2019 prices but went up after Xmas.
960 series for $400.
https://www.amazon.com/iRobot-Roo…101&sr=8-3
E5 (5150) series for $280.
https://www.amazon.com/iRobot-Roo…488&sr=8-3
675 series for $200.
https://www.amazon.com/iRobot-Roo…543&sr=8-3