The invention presents a method for conducting an on-line bidding session to accumulate a collective bid for a property. The bidding session is conducted over a computer network that includes a central computer, a number of remote computers, and communication lines connecting the remote computers to the central computer. According to the method, at least one bidding group is registered in the central computer. The bidding group can be an association, institution, or group of investors formed for the purpose of bidding together for the property. The bidding group has a total bid for the property which is tracked in the central computer. The central computer receives bids entered from the remote computers by members of the bidding group. Each bid includes an individual bid amount which is contributed to the total bid of the group to accumulate the collective bid for the property.