Hi Michael and Sasha,
I am sorry for your frustration. I have found a Smart Lock System developed by a software engineer called The Airlocking System. It might be the answer to your difficulties.
I am cutting and pasting a description from their website for your information:
THE AIRLOCKING SYSTEM:
INSTALL LOCK AND HUB:
AirLocking ships you a Smart lock system. You just need to connect the system to the internet and follow the straightforward instructions to install the lock.
GUESTS RECEIVE DOOR CODE:
AirLocking automatically emails your guests' door codes in advance of their trips along with other check-in information you wish to pass along. You are copied on these emails for your tracking.
LINK WITH AIRBNB CALENDAR:
AirLocking seamlessly links with your Airbnb calendar to track reservations. The AirLocking portal provides status information and allows you to control guest notifications.
LOCK UPDATED WITH CODES:
AirLocking enables the door code in the lock at check-in time and disables it after checkout time. AirLocking also allows you to have codes for your own use which are separate from the guest codes.
CHECK-OUT BUTTON: (Patent Pending)
Airlocking has added a new feature--a CHECK-OUT BUTTON. When guests leave, they are asked to push this button. Instantly, the Host is alerted to their departure and can proceed with Cleaning Services or Repairs.
Best wishes, Heather