An inventory management system includes pick stations, automated vehicles having an onboard power source, a first drive system configured to horizontally displace the vehicle, a second drive system configured to vertically displace the vehicle along a guide system, and a platform for supporting an item during displacement of the vehicle. A first plurality of storage locations store inventory items at a first zone of vehicle operation and a second plurality of storage areas store inventory items at a second zone of vehicle operation. A first pick station is closer to the first storage locations than to the second storage locations, Vehicles are configured to transfer a selected item from one of the second plurality of storage locations to the first pick station or to transfer the selected item from the second plurality of storage locations to the first plurality of storage locations.