I try not to poison mice. Sadly really easy to kill owls that way.
I have a handful of snap traps in the attic and and working on a multikill solution. There is no magic Sadly. There is a balance between price, capacity, smell, quick death and safety. Bucket trap of some variety is cheap and effective. For exterior use a handful of snap traps in a box with access hole works well. Keeps the cat out of the traps and doesn't need to be reset as often as a single trap. For placing in soffit, something like the mouse delete-r is small, effective, high capacity and shouldnt smell much as you arent dumping them in liquid. Pricy bugger though. A24 has similar properties.