Years ago a friend told me about putting dryer sheets in every drawer, closet, storage space. I did that for several years with great success. I learned two things along the way: they needed to be a brand name. (why the generic didn't work that one year still baffles me.) And you need to get all spots. One year I missed one storage bin: no droppings anywhere else..just that bin.
Hope that helps.
Minnesota Mama