I'm in the same camp as RyanB and Rob Grabon.

You should be charging a fair fee for everything you do. If this is true, there's likely a minimum charge to roll the truck, and if it must go back because they didn't do what they promised, didn't have the instructions they promised, they get to pay again for a truck roll.

If you are so busy, that you can afford to send away customers that pay, then perhaps it is time to raise your prices. Otherwise, as long as they pay on time, and pay the fees agreed to, then if they are having a relative do something they likely wouldn't have paid your price for in the first place... I don't see the issue.

If you feel like they've been walking all over you, then you've learned a lesson. I loved my grandmothers saying "You can get walked on, without laying down first!" Her tough love, was to teach me that if I feel taken advantage of, it's because I allowed it to happen... So don't do that!

Asking for the fees you need for every part of what you do, is just good business practice. Doing anything else will get you bitten sooner or later, and the only question is how badly bitten you will be, and how peeved you'll be at the customer... when you should be just as mad at yourself.