Walmart offers the Neato Robot Vacuum Cleaner, model no. XV-12, for $189 with free shipping. That's the lowest total price we've seen for a new vacuum and a current low by $91. This system works on most floors and features a laser-based Room Positioning System that allows it to avoid obstacles while vacuuming a room.
Also available is the Neato Robot Vacuum Cleaner, model no. XV-12, bundled with the Neato XV Series Pet and Allergy Replacement Filter 2-Pack, model no. 900-0080, for $199 with free shipping. That's tied with our June mention and $89 below the lowest total price we could find for these items separately elsewhere.