This company make a beefy lockbox that runs on bluetooth (for long battery life) via separate wifi hub. I think it would be possible for O.R. to integrate with this for generating codes. I have an old farmhouse door so not easy (nor would it look good) to put one of those modern smart locks on it, so I just hung this smart lock box on the door knob! I'm sure there are also many others that don't want to go through the trouble of installing a smart lock.