The user options in QuickBooks Online aren't as limited as you're describing. You can choose between a Standard User, Company Admin, and Time Tracking Only. A Standard User can have full access, no access, and limited access to your Customers and Vendors. You can choose if they have access to only Vendors or only Customers without giving them admin privileges. The Company Admin has access to everything you as the owner does. As for the Time Tracking Only user, they're Vendors and Employees who can only view their timesheets. You can check out this article about QuickBooks users for more information.
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