As Linda said, that is hard to know without more information. Will you be working the old AR and denials, etc, or just from the point where you sign on with the account, and the office will handle all the old stuff? How are the docs with their coding skills? The person that is submitting the claims, are they up on modifiers, etc? Who is entering the patient demo and insurance info into the computer, and are they accurate with that? The answers to these, and other questions(such as what method you will use to do insurance verification), will determine how much time you will need to work the account. On the one hand, you may only need 20 hours a week to work the account or less, on the other hand, you may need 40 hours or more. If you low ball your flat fee, you could find yourself working like a dog for less than minimum wage.