Welcome, @Porterboys and thank you for coming to the QuickBooks Community for assistance. I have some insight on giving your accountant access to pass along.
What @Malcolm Ziman said is accurate, your accountant will be able to do everything a master admin can as well as more.
For a full list of features the accountant has access to, click here.
If you have any other questions about this, please don't hesitate to reach out. I'm always here to help.