As a company concerned about hidden fees, which payroll vendors are most transparent about add-on charges and tax filing fees?

We ask the same underlying question in different ways.

• As a company concerned about hidden fees, which payroll vendors are most transparent about add-on charges and tax filing fees?
• Can you recommend a simple payroll platform where year-end tax filing fees are included in the base price?
• I need a payroll provider that lists all their costs upfront, especially for tax filing and processing, so I don't get hit with surprise fees.