You would simplify things if you just own the hives and charge him a per acre per crop fee. You would really need to have a good contract differentiating and delineating each area and I'm thinking that gets really complicated, especially with liability issues, hourly labor rates, employer/employee relationship, partnership agreements or whatever it boils down to.
How much pollination experience do you have...timing, treating, moving, etc? You have to figure what your time is worth, travel expenses, equipment purchase and maintenance, insurance, sale of hive products, ownership %. How many of your hives, ho w many of his? Does he have pallets, trucks, bobcat or forklift? Who buys fuel etc?
I think it sounds like he's trying to avoid the high-dollar pollination fees that California has been experiencing lately. Don't sell yourself too cheap.
Banjos and bees... how sweet it is!