@Robert5262 I use a August Home lock that uses bluetooth to connect to an app on your phone. I've been using it for the whole time I've been short terming and have only had 2 people that wouldn't use it. No problems over 3 years.
Have you made up your mind on which smart locks to use for your listing? Have you found a suitable solution already?
One of our lovely Hosts @Veronica824 has elaborated here their experience with another brand of smart locks hereincase you were looking for tested solutions.
Have you given a thought to @Robert5262 's suggestions as well?