1. A method, comprising the steps of: providing, in at least one computing device, item classification data that associates each of a plurality of item classifications with a corresponding set of attributes from a plurality of sets of attributes; obtaining, in the at least one computing device, a selection by a user of one of the item classifications from a client computing device; generating, in the at least one computing device, a first user interface that includes a listing of the set of attributes corresponding to the one of the item classifications according to the selection, the first user interface being configured to obtain at least one input value for the set of attributes from the user; sending, in the at least one computing device, data including the first user interface to the client computing device; obtaining, in the at least one computing device, the at least one input value specified by the user for the set of attributes from the client computing device; determining, in the at least one computing device, a suggested price range from a set of historical sales prices in an auction system for a plurality of items that are classified under the one of the item classifications and match the at least one input value for the set of attributes; generating, in the at least one computing device, a second user interface including the suggested price range and a graph of the historical sale prices versus a corresponding value of one of the set of attributes for each respective one of the items; and sending, in the at least one computing device, data including the second user interface to the client computing device.