Need at least the camera, if not that plus a microphone and speakers, not the lock or bell.
Libre Software (Obviously) + End-to-End Encryption
Small and easy to hide, so the camera isn’t stolen, attacked or bypassed.
I use Eufy doorbells, locks, and cameras. I realize they are a Chinese company, but that is almost unavoidable until the US gets back to actually manufacturing tech.
The reason I like Eufy is the local storage and no required subscription fees.