In the fall, and only in the fall, in New England, as it gets very cold, mice tend to make their ways indoors. To combat this we keep the place very clean, no food left out on counters, all dishes put away. In the two years I have lived at this apartment I have done this and only seen one once two falls ago. If you dont do it, and leave food out, then you may invite them in. Otherwise, it has never been a problem.