Sealed buds are usually better for that.

www.investopedia.com/…/sealed-bid-auction.asp

Each party is incentivised to make the highest offer they’re willing to pay from the beginning, as opposed to negotiating the best price they can get.

Additionally, the families forgiving a significant amount of money as part of the bid should factor in, since the responsibility of the estate is to get the best deal, not the most cash.