Chain and lock both tops and sliding side doors, if necessary use metal trash cans, including lids. Store cans indoors at night. Don't let dumpster garbage overflow. Chain the lid down. Bears can easily open most dumpsters.
Fruit trees are a common problem during the fall in Montana.
Bar the windows. Bears can easily push through a glass window. Deodorize with ammonia. Further discourage bears from approaching dumpsters or storage sheds by using loud noise making devices. Fruit Trees and Gardens Fruits and vegetables are not only tasty for humans but among the many natural foods that bears search out in the wild.