Be aware that in most cases it is illegal to charge the customer the fees.
I am fully aware that tons of businesses do it or charge a "convenience fee" which by no means is a legal loophole. They are all betting that no-one will go to the hassle/expense of suing them.
I ran the Accounts Receivable dept for a gigantic corporation and when a CEO wanted to pay a 2.5million invoice with his Amex, I very quickly learned all there was to know about credit cards, the fees associated with them, the legality of passing on those fees and so forth. It is completely plausible that a corporate attorney would take legal action over their corporation being charged many, many thousands in fees, so needless to say, we did not accept his card as we couldn't legally pass on the fees and we didn't want to pay $50,000+ in fees!