You have to be able to explain to them that your overhead is “X” and the cost of a driver for 5 hours (2 and half hours each way) costs “Y”. Keep in mind all of this explained to them may be more than they want to know. Simply giving them as good of an experience as you can will be good enough. Only those that are being difficult will push you to the point you have to give them a balance sheet. With that being said, think about it like a restaurant with a wait staff. If the food is fantastic, they most likely knew that before they came in and they know they are going to pay a premium price for that food. They typically pay that and still leave a tip. They get it and so do your customers if you take care of them.