I agree with Michele. You can bill whatever you want, but the insurance companies have a rate they pay, contracted and/or non-contracted. This amount will differ between carriers as will what is covered and what is not.
The only piece of advice I can give is to let the doctor know that he/she should NEVER bill just the allowed amount, that get averaged into what all the doctors in the area bill and determines the Usual and Customary allowed for the region.
For example, we are in northern California in a fairly rural area. There are still Chiro's charging $15.00 cash per visit. The insurance companies call around and get pricing, average it, and set the allowed amount. Blue Cross allows $22.41 for an Adjust 1-2 areas AND Adjust 3-4 areas, $9.17 for modalities and therapies. We haven't had a raise in the 11 years I've been doing this. The SFO Bay Area and LA have higher reimbursements.