Hello 123BallPoint,
I can appreciate needing to keep an eye on the work being done in your books as you can track changes and get a sense of what's happening in QuickBooks. I have a feature that could work for you.
The Audit Log in QuickBooks Online is a great way to see the various changes that have been made to your books, as well as which user made those changes. The log doesn't show when someone has simply visited a page or views an area, but it'll let you know when someone logged in, when settings have been changed, and when transactions have been created, edited, or deleted. Learn more here: Use the audit log in QuickBooks Online
Take a look at that and let me know if you have further questions.