I usually do the same as Clark, same as my supplier would charge. Never hauled anything that I didn't get paid to put down as well. If I were just hauling something, the charge would be more. Might consider a per mile kind of thing?
'97 Dodge Ram 3500 4x4 - Cummins, ex-cab, dually
'98 Dodge Ram 2500 4x4 - 5.9 gas, reg cab, plow truck
'95 Chevy 2500 4x4 - 350 gas, ex-cab, long bed, back-up truck
2000 Scag Sabre Tooth Tiger, 72", 31 hp Briggs/Diahatsu
2007 Scag Tiger Cub, 48", 19 hp Kawasaki
JD backpack blower
16' Hill Equipment Landscape Trailer