Yes, the industry standard discount given to brokers is 5%. That’s where the broker makes their money. It’s possible, but not likely, that the broker would mark the price up any more than that. Why would anyone pay more to a broker if they can get the flight from the charter company for less?

Credit cards fees vary widely depending on a number of factors. I recommend searching on terms like “merchant account”.

Broker Fees are typical 5-10% of the a/c cost for charter. Most brokers have a Tariff for ground handling and trucking costs, and sometimes they make extra money on these as the actual cost is less than tariff. But they also lose money on these tariffs too, as some places are more expensive than others. The reason that companies use brokers, is that they have access to large amount of carriers, ground handlers, trucking companines. This provides usually the best price for service, and brokers are knowledgeable and in some cases have legal authoirty to submit paperwork for their customers to customs such as entries andshippers export declaritions. This makes it much easier for a company to charter an aircraft as the broker takes care of all the trucking, ground handling, and customs requirements for that shipment, but in turn they charge a fee. It would be a large amount of work to find and arrange all that yourself in a small amount of time.