A computer-implemented method for real-time and continuous inventory management using a multi-level inventory management system comprising peripheral device(s) in data communication with some number of warehouse server(s), aggregation server(s), and sales channel server(s). A warehouse server may employ real-time physical inventory parameters received from a peripheral device to manage stock keeping unit (SKU) counts and locations as shipping orders, purchase orders, and bin transfer orders are serviced. An aggregation server may compile physical it parameters received from warehouse server(s) into available inventory used to service sales orders, reserve orders, and pre-sell orders. An aggregation server may also modify available inventory to address the status of servicing warehouses (e.g., unsellable, sellable, and dropship).