Data is collected and aggregated regarding a particular used item for sale, e.g., automobiles, which is in turn validated and normalized with respect to pre-determined identification models. A historical report may be generated to provide an assessment of value based on qualitative information such as mileage and/or location, and may be presented in a multi-axis graphic format. Data records are collected from a plurality of sources over the Internet, and are validated by comparing data field entries in the aggregate data records with data field entries in an established validation database. The validated data records are normalized with respect to a predetermined set or sets of fields by assigning an identification unit to each validated data record. A web crawler to seek out suitable data records relating to the used items that are sought, a search engine is queried to derive a list of suitable high probability target URLs.