The three ways a lot closes

A timed auction is the familiar one: bids are public as they come, each one has to beat the last, and the lot closes at its stated time. If a bid lands in the final moments the close can extend, so a lot is not won by the clock rather than by the price.

A sealed tender takes one figure from each bidder, and nobody sees another's until the sheet opens. You bid what the vehicle is worth to you, once, because there is no second chance to react. It suits a seller who wants a clean answer and a bidder who does not want a bidding war.

Buy now is a fixed price with no bidding: the first to take it, takes it. Some lots carry it alongside a timed auction, which ends the moment somebody buys.

The mode is printed on the lot before you commit to anything, and it does not change once bidding has opened.