Freo S

The Freo S costs under $500 and still has three useful things: a dock that empties the bin, brushes built to shed hair, and a sensor on the front.

The sensor is the one to notice. The robot maps with a laser, and it has a light sensor on the front for furniture and low obstacles. Only one other robot in our under-$500 band has a front light sensor, which matters if your floor is seldom clear.

The dock saves you the dustiest job. After each run it sucks the robot’s 250 ml bin out into a dust bag of 3.5 litres, and only one robot in our list has a bigger bag. The dock itself is 33 x 22.8 x 16.2 cm. Emptying is all this dock does, so it won’t wash the mop pad for you.

For hair, both the roller brush and the side brush are tangle-free designs. That’s why the Freo S is the budget pick in our pet hair guide as well as in our guide to vacuum and mop combos.

It’s 10 cm tall, so measure under the couch before you count on it getting in there. It gets over a 2 cm sill, and it can hold maps for more than one floor. At 3.2 kg it’s no effort to carry upstairs.

What you give up is cleaning power. Suction is 8,000 Pa, and the mop is a flat pad with 8 N of pressure behind it, fed from a 300 ml tank at one of three flow levels. That’s a match for dust, crumbs and footprints on a hard floor, and it’s out of its depth on thick carpet or a dried spill. Charging the 3,200 mAh battery takes about five hours.

If you’d rather have more suction from the same band, the Xiaomi Robot Vacuum H40 has 10,000 Pa, runs for up to 180 minutes and empties into a 4-litre bag. If your floor is the kind that always has something on it, stay with the Freo S.