well you dont bill at the VA....
you can do obesity but if they have a behavioral health carveout then you need to have an F code
otherwise I just use Z01.818 (pre-operative exam) and Z03.89 (observation for suspected mental condition)
if they have shîtty insurance it won't fly. But remember that the insurance requires the psychological evaluation.
Typically I insist that surgery pay me for these out of their own funds and they can worry about billing. They can get prior authorization for the eval if they want to bill for it (typically you need to get prior auth in order to ensure reimbursement). IMHO they make a huge amount from doing these procedures, need a psych eval, and thus they can pay me for it.
Also, there is not such a thing as psych "clearance". We are not security. It is best not to think of your job in that way or to document as you are "clearing" the surgery for a procedure or you may find yourself liable for the inevitable complications. Instead, I might put something like "There are no absolute contraindications to ___ from a psychosocial perspective. In order to further optimize her candidacy for this procedure I recommend the following:" (there is almost always something to recommend to, even if the pt doesnt have a mental illness.
The only exception is if the indication for surgery is psychiatric (e.g. BSO for PMDD or DBS for OCD etc) - in that case I will highlight where the intervention is warranted, but even then discuss potential risks etc and never equivocally say pt should have the procedure etc.