In sealed-bid auctions, only the auctioneer can see the bids that have been submitted.
The city has been holding these sealed-bid auctions on an ad hoc basis since 1981.
The company won a sealed-bid auction last May for 47 vacant lots remaining in the 79-lot development.
In the two sealed-bid auctions, Hamakua will sell 28 properties.
In an ordinary sealed-bid auction, bidders never offer more than they think the prize is worth.
And sealed-bid auctions will continue for a time after that, market participants said, as the proposed new system is tested and debated.
The family of the collector who bought it is selling it now, in a sealed-bid auction that ends on March 7.
The sale process will be by sealed-bid auction with an expected completion date of "Late Summer".
Yesterday's sealed-bid auction was for 174 corporate medallions, which can be bought only in lots of two and must be used 24 hours a day.
For the sellers, there are thousands more dollars to be made by what agents call "creating excitement," starting a bidding war or sealed-bid auction.