The iRobot Roomba Combo j7+ is the top 2-in-1 pick in our guide to the best robot vacuums, as it adds a retractable mop for cleaning hard floors onto a powerful robovac for carpets and other surfaces. It's expensive at its usual list price of $1,000, but right now you can get it for $699 at Wellbots. Just use the code ENGROOMBA300 at checkout. While that's still far from cheap, it does mark the largest discount we've tracked.
The Roomba Combo j7+ is undoubtedly a luxury purchase, but we found its vacuuming and mopping capabilities to mostly work as advertised. As a robot vacuum, it offers strong suction power, accurate home mapping and intelligent obstacle avoidance, including a strong knack for avoiding pet waste. In its "vacuum and mop" mode, it's smart enough to know when it's rolling over hard floors instead of carpet, then only mop the former. The battery generally lasts between 90 to 180 minutes depending on how often you mop, and the whole thing works with Alexa and the Google Assistant. This model also comes with a (noisy) self-emptying base station, which the vacuum automatically retreats to when it's done cleaning.
It's not perfect: You'll have to refill the water tank fairly often, there's no mop-only mode and the mopping functionality isn't as efficient as just using a Swiffer. iRobot's Home app remains easy to use, but all robovacs require the occasional maintenance and intervention. Still, a device like this makes cleaning more hands-off than it'd be otherwise, so the Combo j7+ could be worth it if your home has a mix of carpet, hardwood, laminate and other surfaces. For more details, check out Engadget Senior Editor Daniel Cooper's write-up of his experience with the device. Just note that, like many robot vacuums with obstacle avoidance, the j7+ comes with a built-in camera. That may raise privacy concerns for some, particularly with Amazon in the process of acquiring iRobot.
A couple of less expensive Roomba 2-in-1s are also on sale. The Roomba Combo j5+ is down to $499 with the same ENGROOMBA300 code, while the standard Roomba Combo j5 is available for $349 with the code ENGROOMBA250. Those are $300 and $250 discounts, respectively, and both represent all-time lows. The Combo j5+ is a newer midrange alternative to the Combo j7+: It has most of the same features, but it lacks the j7+'s retractable mop arm and ability to automatically avoid carpets while mopping. Instead, you have to swap in a vacuum-only bin (or just move your rugs) when you want to clean a carpeted room. You also have to empty its vacuum/mop combo bin manually. The standard j5 is essentially the same device but doesn't come with a self-emptying base station.