Concrete patio blocks around the perimeter of the coup work along with lock them up at night.
Be careful about the racoons, they are vengeful if you kill or injure a relative of thiers. The family will come back and trash something. We had a pet one as kids, and they will open anything that does not have a lock of some sort on it.
And, yes we have foxes as well, our chicken run has kennel wire around it. It gives the dogs time to respond.
We also have coyotes, eagles, hawks and owls, they all like chicken. So we make sure there are things for them to get under quickly as well.