You are right. You can hire an accountant to do your tax’s and you can hire an accountant to do financial statement for you.
When they perform this service they do it in two ways.
One way they come to your business and audit your books and make a financial statement or your tax return for you on their findings. When they are done they put a note with the financial statement or tax return that they audited your books and can verify that the information is accurate.
The second way is you hire them and you provide all the information to them. They never come to your office and verify the information they just use what you have provided. When they are done they put a note with the financial statement or tax return that you provided the information that they used. That they did not audit your books and can not verify that the information in accurate.