Amazon is blowing out Roombas starting at only $170!
Roomba® I4 Robot Vacuum | iRobot | iRobot
Is the iRobot Roomba i4 Worth The Money? - Genymoney.ca
iRobot Roomba i4+ (4552) Robot Vacuum with Automatic Dirt Disposal - Empties Itself for up to 60 Days, Wi-Fi Connected Mapping, Compatible with Alexa, Ideal for Pet Hair, Carpets : Amazon.ca: Home
Costco shows an i4 robot to compare with the i7+ on its site. The link to the actual listing for the i4 does not work though. It appears that the i4 somehow systematically maps, but without a camera/vslam. : r/roomba