GearBest offers the Xiaomi Mi Robot Vacuum Cleaner for $329.99. Coupon code "XIAOMIVAC" cuts it to $299.99. Plus $8.51 for shipping, that's $28 under our April mention and the lowest price we could find by $50. It can be controlled via smartphone app and can clean for up to two and a half hours per charge.

Note: This item ships from China and may take two to five weeks to arrive.