What should I charge?

You should charge for extra stops. Even as company driver i was paid extra for additional stops.

 

If the truck moves, it's going to cost someone money.

If he wants it free because it is so close, they can come pick it up......

 

You should at least charge the guy $120 an hour from the time you arrive at the first stop

 

How often does this happen?

Is this a good customer and a long time client?

 

If you have an established relationship with the owner it's probably best to work something out. Especially if this is a rare event. Talk to the guy and I am sure you both will make something work.

 

Each pickup and delivery is an opportunity for delay or other issues, especially jobsite delivery's. Time is money

If you choose to do it for free now, good luck ever getting paid for it in the future

 

You should always have a limit of what is your bottom number and use that number as a guide, don't offer it to a customer but rather shoot higher and act like you are losing money or breaking even, for some reason when they think they've got you cornered they agree to the work.

And get it in writing.