We have mice here also. We use the ones where they eat and go away to die and leave no smell.
We have to keep the throw ones in the roof as we always have them there and nothing is worse than hearing a mouse in the walls in the night.
We also have them outside under the water tank but the gap isn't big enough for the dog to get them. The one we found outside dead was quite large. YUK!!!

I think it has something to do with the good weather we have been having.