A pre-auction offer brings the auction forward. It does not replace it, and it is usually unconditional.
Buyers often ask whether they can make a conditional offer before the auction to avoid competing. In practice the vendor accepts the offer as a reserve, the auction is brought forward, and everyone else gets to bid against you. The offer has to be unconditional to be accepted at all under most auction rules.
We don't recommend making a pre-auction offer. Get ready to bid on the day instead.
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