Thanks for joining this thread, @GrovesCleaning.

Currently, it isn't possible to log out a specific user on your end. The owner of the login credentials should be the one to log off so that the next person can access QuickBooks Desktop (QBDT) using their login details. 

You might want to learn about hosting and multi-user mode. Feel free to read this article: Host your company data in multi-user mode in QuickBooks Desktop.

Let me know if you have more queries about managing access and login credentials for your users by replying to this post. I'll be willing to help. Have a good day.