Auditing Records Reimbursement

I am starting an audit of reimbursement for providing financial records. So far I've found Regulation S and some other regulation but it only applies to government requests. I would like to expand the audit to look at how we charge our members when they want copies of previous statements or transaction documents. Does anyone know if there is any regulation on this and where to find it? I'm from NY if anyone knows of any state-specific rules.