Abstract: The present invention pertains to systems, methods and devices for online reservation inquiries of individual shares of an item. The system has a server that makes available a 3D graphic model of the item as well as reservation statuses of the shares of the item for inquiries, and a client computer for displaying the 3D graphic model on a user screen from an arbitrarily changeable perspective. The 3D graphic model of the item contains a graphic object for each share that is spatially related to this share in the 3D graphic model. The server transmits the 3D graphic model of the item and the reservation statuses of the shares of the item to the client computer in response to respective inquiries. The manner in which each graphic object is displayed in the arbitrarily changeable perspective of the 3D graphic model is defined by the reservation status of the share to which it is related.