Tough question. A lot depends on whether you are trying to make a decent profit or are providing a good will service with only minimal profit. Consider, you have to haul, do the work and, maybe, deliver. Plus your machinery must be amortized. Also consider what happens if you make a mistake and mess up their wood. Off the top of my head, I would suggest $50.00 an hour, not counting hauling, with a $20.00 minimum. e.g. one board planed, five minutes = $20.00. Let us know how it works out.
"Folks is funny critters."
Think for yourselves and let others enjoy the privilege to do so, too. ~Voltaire