Two ways a house changes hands
In a private treaty sale, buyers make offers and the seller negotiates. Offers can carry conditions, and in most states the buyer gets a short cooling-off period after signing.
At auction, the seller sets the terms in advance and buyers bid in public. The highest bid at or above the reserve wins, and the winner signs an unconditional contract on the spot.
Private treaty: offers and conditions
A written offer usually covers:
- Price and deposit. How much, and how much is paid at exchange.
- Conditions. Common ones are finance approval and a satisfactory building and pest inspection.
- Settlement period. Sometimes worth more to a seller than a few thousand dollars.
Conditions protect the buyer but make an offer less attractive to the seller. A clean offer with fewer conditions often beats a slightly higher one with many. The trade-off is risk: dropping a finance or inspection condition only makes sense once that work is actually done. Your mortgage broker can tell you where your finance stands, and a solicitor or conveyancer should review the contract before you sign.
Cooling-off by state, as at October 2026
| State | Cooling-off period | Cost to withdraw | When it doesn't apply |
|---|---|---|---|
| NSW | 5 business days after exchange | 0.25% of the price | Auction, or exchange on auction day after a pass-in. Can be waived with a 66W certificate. |
| VIC | 3 clear business days from when the buyer signs | $100 or 0.2% of the price, whichever is greater | Auction, or within 3 clear business days before or after a publicly advertised auction |
| QLD | 5 business days from receiving the signed contract | Up to 0.25% of the price | Auction, or a contract made within 2 business days after an unsuccessful auction if you were a registered bidder |
| SA | 2 clear business days from receiving the Form 1 or signing, whichever is later | The seller can keep up to $100; the rest of the deposit is refunded. Confirm with your conveyancer | Auction, or later the same day. Can only be waived with an independent lawyer's certificate. |
Cooling-off is a safety valve, not a strategy. We treat any offer as a commitment the client is ready to keep.
Auction: what changes
- No cooling-off. In all four states, a house bought at auction is bought.
- No finance condition. Finance needs to be in place before the day, in a form your broker confirms suits an unconditional purchase.
- Deposit on the day. Usually 10%, paid when the contract is signed.
- Due diligence comes first. Building and pest inspection, contract review and pocket checks all happen before the auction, at the buyer's cost, with no guarantee of winning.
- Registering to bid. NSW, QLD and SA require bidders to register, with ID in NSW and SA. Victoria's rules differ, so we confirm with the agent.
- Vendor bids. The auctioneer can bid for the seller within limits that vary by state (one in NSW, up to three below the reserve in SA, and only up to the reserve in QLD). They must be announced.
In Victoria, auctions held from 16 October 2026 must have the reserve published at least seven days before. That changes the auction day considerably, and we'll learn how agents adapt.
Pre-auction offers
Many auction campaigns will entertain an offer before the day. A seller usually wants a strong, near-unconditional offer in return for cancelling the auction.
We make one when the comparables support the price, the client's written limit allows it, and taking the house off the market removes real competition. We don't when the agent is clearly using the offer to set a floor for the auction. Note the timing rules: in Victoria an offer accepted within three clear business days of the auction has no cooling-off, while in SA a successful pre-auction offer does.
Bidding basics
- Know the number before you arrive. The walk-away price is written down beforehand, not worked out on the footpath.
- Bid clearly and calmly. Confidence matters more than speed.
- Watch the reserve. If the house is passed in, the highest bidder usually gets the first chance to negotiate. That can be the best position at an auction.
- Never bid against yourself. Sounds obvious. Happens surprisingly often.
How we approach each
The research doesn't change: suburb, pocket, house, comparable sales, inspections and a signed limit. What changes is timing. Private treaty rewards patience and clean terms. Auction rewards preparation and discipline. Our guide to what a buyer's agent does explains who bids and who decides, and the calculators show whether the holding cost still works at the top of your range.
Sources
- NSW Government, "Contracts and deposits when buying property in NSW", updated September 2025
- NSW Government, "Buying property at an auction", updated July 2026
- Consumer Affairs Victoria, "Buying property by private sale", September 2022
- Consumer Affairs Victoria, "Buying property at auction", May 2021
- Consumer Affairs Victoria, "Understanding property prices and underquoting for buyers", updated October 2026
- Queensland Government, "Cooling-off period", accessed October 2026
- Queensland Government, "Buying property at auction", October 2024
- Government of South Australia, "Offers, auctions and buying off the plan", updated March 2026
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