I've just entered a race in France and the cost of the half marathon is €14. The 10k is €8. This is fairly typical pricing for French races.
It's marked, marshalled, water-stationed (and there are usually bits of cake and dried fruit, too), and there's a t-shirt for finishers.
There are loads of cups, and about €3,800 worth of cash prizes.
There are no DJ's or music, but I don't look for those in a race!