Thank you so much for your input. I see where you are coming from about the price of a cleaning and you make some really good points.I think a mobile trailer for gun cleaning isn't a bad idea, but I don't know that I would pay $40 per gun. If this is a vehicle to bring business back to your shop for additional cleanings, gun smithing, training, etc, then you might consider the cleanings as a loss leader of sorts. Think about your price and your target market. Also, if I were going to have you clean my gun(s), I'd want it done while I wait at the range.
Keep in mind that your target market might not be people like you find on this site, who are more dedicated gun enthusiasts. Your target market is more likely the beginning or non-obsessive shooter. Someone who owns a single gun, and goes to the range a few times a year for fun. Someone who never knew they needed to clean a gun. Yes there are idiots out there, and you have an opportunity to make money off of them.