I NEVER use bait (Decon or peanut butter are attractants) to kill mice. Peanut butter will just attract more mice as it can be smelled by mice from a great distance. Make sure your unit has all the holes sealed. I then put moth balls at the feet of the jacks, tires or anything that touches the ground. There is little smell to you. But any pest will avoid going near the moth balls. It has worked for me for the last 3-4 years after having an enormous problem.