1. A sales portal system supporting a plurality of buyer computers used by a corresponding plurality of buyers, the sales portal system comprising: a server system communicatively coupled during operation to: a first seller's computer used by a first seller to support sales of a product, the product having a first description and a first price, both the first description and the first price being stored in a first database on the first seller's computer having a first storage format; a second seller's computer used by a second seller to support sales of the product having a second description and a second price, both the second description and the second price being stored in a second database on the second seller's computer having a second storage format that differs from the first storage format, and the first seller being a competitor of the second seller; and one or more of the plurality of buyer computers, wherein: the server system responds to a query received from one of the plurality of buyer computers by delivering a first seller rating and a second seller rating, the first description and the first price from the first database, and the second description and the second price from the second database, to the one of the plurality of buyer computers, including reformatting at least two of the first description, the first price, the second description, and the second price; and the server system managing a sales transaction of the product from one of the first seller and the second seller as identified by the one of the plurality of buyer computers.