eBay with Roborock has the certified refurbished Roborock S7+ Robot Vacuum and Sonic Mop with Auto-Empty Dock (Black) for $536 - 15% off with coupon code SAVE4SPRING23 [Exp 3/20] = $456 with free shipping. Features ultrasonic carpet detection, auto lifting mop, intelligent map routing, and 2500Pa of suction.