10
Presence detection
(feddit.it)
The Aqara FP2 is discounted for Prime Day in the UK too, £70.54 down from £82.99.
They are still a lot cheaper from sites like AliExpress however, around £40-£45 if you don’t mind waiting a bit longer for shipping.
Hopefully mmWave sensors will start falling in price soon, the tech is impressive but the cost is currently quite prohibitive compared to IR sensors, especially if you have a lot of rooms.