The lawyers rules are real clear. You have to give the client the file, especially if he’s a criminal case defendant and withholding the file might impair his ability to defend himself.
Hypothetical: I am an attorney working a case and I hired a consultant to brief me on a topic that is relevant to this case and others that I may work on in the future. Are my notes on this consultant's work part of the file if I did not bill my client?