You might want to check out the keypad device type that was updated by zcorneli. It has a beep compatibility and exit delay beeps. With a little coding magic you can use the beep as the door chime. I’m working on adding it and the exit delay into the smartapp I use.
https://github.com/miriad/SmartThingsPublic/tree/keypad/devicetypes/mitchpond/centralite-keypad.src
You can also see more of the conversation here starting at post 738. CentraLite Keypads