We used to have a live trap for mice at the last place I worked...a big plastic rectangular tube with a hinge door that only opened from the outside. You put food inside, mouse goes in, can't go out, and when you caught the mouse, you could get rid of it without killing it. They were pretty cheap.
Of course, there was the one time the owner's wife forgot to tell us that she re-baited the trap. Don't want to talk much more about that one....
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