If I have Sales Staffs that only uses Estimate, Invoice, SOA. Inventory Which User Role should I give them?

I'd be your guide to ensure you select the appropriate user role for your sales staff, CS.

You can choose the Standard limited customers only role so your sales staff will have access to estimates, invoices, and inventory. However, this has limited access to reports. For reference, check this article: User roles and access rights in QuickBooks Online.

Once ready, follow these steps to proceed:

1. Select the Gear icon and click Manage users.
2. Next, click the Add user button.
3. Enter the details in the First name, Last name, and Email fields.
4. In the Select a role dropdown, choose Standard limited customers only.
5. Once done, click Send invitation.

You can read this guide for additional information: Add and manage users in QuickBooks Online.

Moreover, adding users will depend on your QuickBooks Online (QBO) subscription. To know how many billable user you can add, read this link: Learn about usage limits in QuickBooks Online.

Should you need additional information about the managing user access, please post a comment below. I'm just around the corner to assist. Have a good one.