The key is to leave the traps in their path. How do you know their path? My brother-in-law’s parents were exterminators (they retired and sold the business). He basically told me that mice have no sphincters so whatever they eat goes through their system pretty quickly and you’ll see droppings almost on the spot. I bought 2 rat zappers when my apartment was having problems. All I did was put in batteries, set it in their suspected path. When the “mouse caught” light was blinking I turned the trap over into a bag and reset the zapper.
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