If it helps in your figuring, I see about 55% 99213s, 35% 99214s and 10% 215s. I am a .8 FTE and I see an average of 90 visits a week. I bill about 90K a month for the practice, give or take, depending upon how many procedures I do. Even accounting for my part-time status, I am not nearly the biggest earner in my practice mostly because I see a lot of well children. Go for sick(er) adults with multiple co-morbidities and you will bill a larger number of 99214s. If I were concerned about that issue, I would not opt to do well child visits, lol. As it is, they are the highlight of my day!
In defense of my productive colleague referred to above; he is not popular, but he is one of the most gifted diagnosticians in the field. He has a subspecialty in lipid management, so he does get a lot of supersickies, and can nail them for multiple diagnoses (dyslipidemia, HTN, DM, macro/micro vascular dz, renal failure, etc). People go see him for his expertise in spite of the fact that he is a bit of a jerk, lol. He is a scientist foremost. I think the fact that he gets it right the first time and spares them the tedium of his company on multiple visits is a plus.
People also like it that he is on time. More dependable than the MAX train! If your appointment is at 9:00am, I think there is something appealing about being seen at 9:00am and out the door at 9:10!
I don't have any experience negotiating that kind of contract, but somewhere on this site David has given outstanding advice on that in the past. I am sure if you search you will dig it up.