Hours includes difficulty of extraction and amount of work the customer wants to take on.
I usualy want to get the brush out of my way, so I will jump at the chance to leave the logs where they lay and/or fine raking. Loggs too big for thier chainsaw, extra to cut to firewood length.
Tree work is very subjective to the workers methods and willingness to damage property. You may get a real lowball offer, but these guys will leaves huge divots and tracks from thier skid stears. Unless the soil is bone dry, there will be some sort of marks. Driving a truck on the turf is another one...
In low impact operations, if the tree is near the road or drive and the limbs can be rigged right to the infeed of the chipper...
Then when you look from region to reggion, workmans comp can be from 20 to as high as 40% of gross payroll!!!!
idiot factor of the customer can apply
My buddy had a customer who wanted the firewood, he gave a good price, we show up for work and the guy wants stuff to 1 inch!!!!