A system and method for constructing data concerning items of an asset. The method comprises: providing a user data entry interface; receiving a plurality of data values, each into a data field of the interface, wherein the plurality of data fields comprise a specification for the item and each data field of the specification describes an attribute of the item, and storing the specification into a database on a computer system. The system includes a data store for item specification data provided on a host computer coupled to a network; and a data input toolset comprising at least an item type manager and an item specification manager.