Smart Lock - HA integration and Geofencing without a phone?

Hi All

Fairly new here, and to smart home setup. Just moved into a new home and have a disabled relative with Parkinsons that presents a lot of challenges.

One thing I’d like to introduce is a Smart Lock, preferably with Home Assistant integration, that can automatically lock when he leaves the house and unlock when he returns.

The challenge is that he doesn’t have a mobile phone, he doesn’t remember to take keys (and therefore doesn’t remember to lock the door either).

The one thing he does always remember though is his tablet box. So my intention was to stick something to the box, like an RFID card or an AirTag or similar type of device - and then create an integration that detects when the device is in range of the door to unlock it, and lock it when it goes out of range. (if this means it locks the door while he is inside that isn’t an issue).

So I’m looking for advice on any particular model of Smart Lock that can cater for this - ideally other features would include PIN & Biometrics, and Smart App integration for us and visitors.

Thanks in advance