We have been using various smart locks for years at home and properties. Schlage and Yale are excellent ones, two of the ones we like the most:
Yale:
https://www.amazon.com/dp/B00HS1O77G
Schlage:
https://www.amazon.com/Schlage-Connect-Touchscreen-Deadbolt-SmartThings/dp/B00AGK9KOG
Personally I prefer the Yale lock since it has better battery life but very happy overall. The Schlage lock hsa a few more security features which we use in our house but for the rental property, we prefer the Yale lock which has all the features we need and it's very reliable (the Schlage battery needs to be changed once it hits 50% where as with the Yale we are safe all the way down to 20% through we try to change it sooner if possible).
As for managing the users, we have been using them with SmartThings to program them remotely using RBoy Apps (you can check them out at www.rboyapps.com)
They also have a low battery app to inform us when the lock battery needs to be changed (about once in 4-5 months).
For almost 2 years we had been using their lock code user management app which allowed us to manually program the users and set start / end dates so we could program this weeks/months ahead and forget about it. Come time and it would activate the user codes and then delete them when the stay was over.
We could also set it up to turn everything off (HVAC, lights and turn on the cameras) when the renters left (the app takes cares of all this). It's been very reliable (barring a few internet connectivity issues) and the support is great. This is the original app:
https://community.smartthings.com/t/release-door-lock-code-lock-user-management-create-delete-and-sc...
However, with their newer version called Rental Lock Automater that automatically connects to the airbnb property calendar, schedules the users and even sends them a customized text message, we can't say enough good things about this app. Basically it's completely hands off user management for us. You can find more details here:
https://community.smartthings.com/t/release-rental-lock-automater-automate-user-codes-with-airbnb-ho...
I just love how reliable and comprehensive this app is it's been competely bliss for us especially with peak season coming up.