For internal medicine there are way too many cpt & dx codes to list. They are the usual E&M codes with additional codes for testing depending on what services are provided. I'm not sure what you mean by "bundling & unbundling codes". There aren't codes to bundle or unbundle, but codes are sometimes "bundled" by the insurance carrier depending on how the claim is coded and the plan's guidelines. One claim may be bundled with one insurance carrier but not with another, based on the plan. It is not ok to specifically code a claim to avoid bundling. The claim should be coded as the services were performed.
All of the other questions you are asking all have too many variables. What part of the country, city or rural, how many providers seeing patients, how many hours/days are they open?
Sorry I can't be of more help!