Brent Hrabik, MD

It sounds like you are set up like I did in Kansas with another
doctor.  We are in 1750 square feet. We also are separate
corporations that basically share office space and employees.  We
will each fund the office corporation for employee expenses,
injectibles we used, supplies etc.  We are using quick books to
manage the 3 companies. 
It has taken about a year for us to work out kinks with our lab,
billing service, ultrasound, xray etc. 
The capitation check can be nice, but it is very good to be
diversified.  Staying in the same space I am sure is pretty cost
effective for you if you can keep phone systems and other things
that the others will all want new. 
Good Luck and Keep Hanging In there.  I am still learning more about
coding all the time.