It would depend highly on how well equipped the logger is. Here on the west coast, a 50-50 split is pretty common, with the logger picking up all of the logging and hauling costs, and marketing the wood to the mill.
Here's some things to watch out for:
1.- Don't just hire a "house" logger, meaning a logger who is the 'main man' for a particular mill. Reason being, he'll quote you a lower price for the sale of the wood delivered to the mill, then the mill gives him a kickback for doing so. I have seen loggers here quote a landowner $450/mbf for good standing 2 and 3 mil Douglas fir, when the mill was actually paying $625/mbf. Then they split the additional profit with the logger.
2.- Watch out for loggers who sub contract a lot of the work. It's one thing if a logger hires a faller or a pair of fallers, and then has a crew that does the main part of his logging. However, in recent years, I have seen loggers sub-out practically every part of the job, basically the logger is making money just acting as a manager. There's not a problem with that except you always get lower quality work when you sub everything out.
3.- The best loggers are involved in every stage of their contract. The best of the best loggers are actually good foresters first, and loggers second. That way they have the know-how to cruise standing timber, getting a good idea of the volume and grade of wood involved. Most loggers you'll ever meet don't know how to use a diameter tape, increment borer, relaskop, basal prism, or a clinometer- all valuable tools for a planning forester.
The first step is to contact local mills that process the kind of wood you have on your property. More than likely they'll be willing to send a company forester to your place to look things over. Most of the time the company forester also doubles as a log buyer, so he or she can give you an idea on the spot how much your wood is worth. They can also give you the best local options for logging your property.
The landowners that make the most money are they ones that have the time and ability to do their own logging and hauling. However it turns into a more than full time job for the landowner, and it is a lot of work.