Refer to this thread for the official release which does not seem to be imminent.
As far as being able to set up temporary codes for rentals, you could use the smartapp change-lock-code (see my github)
to delete a specific user after a while.
But, if you’re willing to pay for more advanced lock code management, you’ll find more lock management capabilities within
the following thread (at the end). Some specific smartapps were developed by a fellow developer.