ferrets work great on rats but they can't get into mouse holes.
Best idea is to alternate between traps and baits. So by the time they start to wakeup something no good for them they are gone.
I use the wax block baits as they are less likely to be eaten by birds.
If I lay baits outside I tie them in the middle of a bit of plastic downpipe to keep them away from the birds and dogs etc.