Wiki add on code rules

Too general a question.... Can you please let us know how you are planning to use these codes, and why you think it does/does not apply to the way you want to use the codes?
Billing as an ambulatory surgery center - the add on codes are almost always paid using the multiple procedure discount. Sometimes they are not but then if there is an audit by the insurance company they ask for the $'s back.

I'm assuming these rules for the "add-on" codes do not apply to ASC's.