RE: How much for IL hunting lease?
20 acres is not very much room. Going rate for NC Il is around $10-15/acre.
You give up your control when you lease. You also take on liability for anyone hunting there.(Because you are taking money)
As the guy above said, you may just want to allow one/two guys to bow hunt it in return for some help in watching the farm, planting foodplots, hanging stands or help at home.
Good luck!