Property due diligence
Sale method and commitment point
Private treaty, pre-auction offer, auction — when each one legally binds you, and what that means for whether you can still negotiate conditions.
Key points
- A private-sale buyer becomes bound when both parties sign the contract of sale.
- An auction buyer becomes bound the moment both parties sign, immediately after the hammer falls — with no chance to negotiate terms at that point.
- Only a private-sale or pre-auction buyer can negotiate conditions like finance or a building and pest inspection; an auction buyer can't, without the seller's agreement.
- A pre-auction offer signed close to the advertised auction date can lose cooling-off protection even though no auction actually took place for that buyer.
The table below uses Victoria's own cooling-off length and exclusion rules as the worked example — every state has the same basic three-method structure (private treaty, pre-auction offer, auction), but the specific cooling-off length differs by state; see the cooling-off comparison guide for all 8 states and territories (e.g. NSW's is 5 business days (NSW Department of Customer Service (in collaboration with NSW Fair Trading), verified 12 Aug 2026), not Victoria's 3).
Three sale methods, three different commitment points
In an agent-managed private sale, a buyer makes an offer by signing the contract of sale, which the agent takes to the seller unless instructed not to (Consumer Affairs Victoria, verified 30 Jul 2026). There's no legally binding contract at auction until both buyer and seller have signed it (Consumer Affairs Victoria, verified 30 Jul 2026) — for the successful bidder, that happens immediately after the hammer falls. A pre-auction offer follows the private-sale process, but if it's signed close enough to the advertised auction date it loses the cooling-off protection an ordinary private sale would otherwise carry (Consumer Affairs Victoria, verified 30 Jul 2026) (Consumer Affairs Victoria, verified 30 Jul 2026).
What each method allows you to negotiate
A private-sale buyer can negotiate conditions — loan approval naming the lender, the sale of an existing property, or a satisfactory building or pest inspection. An auction buyer cannot add conditions like these without the seller's specific agreement (Consumer Affairs Victoria, verified 30 Jul 2026). That single difference is why due diligence has to be fully complete before an auction, but can sometimes still be finished under a negotiated condition in a private sale.
Scroll sideways for more columns
| Sale method | When you're bound | Cooling-off? | Conditions possible? |
|---|---|---|---|
| Private treaty | When both parties sign the contract | Usually — 3 clear business days, subject to exclusions | Yes, by negotiation |
| Pre-auction offer | When both parties sign the contract | Often excluded if signed near the auction date | Yes, by negotiation |
| Auction (on the day) | Immediately after the hammer falls, on signing | No | No, unless the seller specifically agrees beforehand |
| Passed in, post-auction | When both parties sign a (possibly amended) contract | No — the cooling-off auction exclusion still applies | By negotiation with the seller |
Worked example
A buyer is deciding between making a pre-auction offer or waiting for auction day on a property scheduled for auction in ten days. Because a pre-auction offer signed now would fall outside the 3-clear-business-day exclusion window, it would carry a normal cooling-off period and could include a finance condition — an option that disappears entirely once the property goes to auction.
Common mistake: assuming "no auction happened for me" means cooling-off applies. It's the timing relative to the advertised auction date that matters, not whether the property actually sold under the hammer.
What changes in 2026 and 2027
Victoria's Consumer Legislation Amendment Act 2026 became law on 8 September 2026, and its price-disclosure changes start on 1 October 2026 (Parliament of Victoria, verified 27 Sep 2026). For auctions and fixed-date sales held on or after 16 October 2026, the agent must publish the seller's reserve price, as a single dollar figure, at least 7 days beforehand, and the sale can't go ahead if that hasn't happened (Consumer Affairs Victoria, verified 27 Sep 2026). A pre-auction offer is still treated as a private sale and isn't held to that 7-day wait, but inviting offers by a set date and time can count as a fixed-date sale that is (Consumer Affairs Victoria, verified 27 Sep 2026). From 1 June 2027, the Section 32 vendor statement must be available within 14 days after a private sale is advertised, or at least 14 days before an auction or fixed-date sale (Consumer Affairs Victoria, verified 27 Sep 2026).
Practical checklist
Before you decide how to proceed
- Confirm the exact sale method being used for this specific property
- If it's a pre-auction offer, check the advertised auction date against the cooling-off exclusion window
- If conditions matter to you, confirm whether the sale method allows you to negotiate them
- Open your due-diligence file before, not after, you're asked to commit
Relevant Delora tool
Want this as a checklist for your own purchase? Start free in the Delora app
Questions for a professional
- Given this sale method, when exactly will I become legally bound?
- Can any conditions be negotiated here, or does the timeline require me to be ready to commit unconditionally?
Official resources
- Consumer Affairs Victoria: Buying property by private sale
- Consumer Affairs Victoria: Buying property at auction
Important limitations: This is general education about how Victorian sale methods work, not personalised legal advice. Confirm the specific contract's terms and your actual commitment point with a licensed conveyancer or solicitor. The three-method structure is universal, but exact cooling-off timing differs by state — see the cooling-off comparison guide for all 8 states and territories.
Sources and methodology
- Buying property by private sale — Consumer Affairs Victoria (retrieved 30 Jul 2026, last checked 7 Aug 2026). Licence: CC BY 4.0
- Buying property at auction — Consumer Affairs Victoria (retrieved 30 Jul 2026, last checked 7 Aug 2026). Licence: CC BY 4.0
- Contracts and deposits when buying property in NSW — NSW Department of Customer Service (in collaboration with NSW Fair Trading) (retrieved 12 Aug 2026). Licence: NSW Government content, reproduced for research/citation purposes
- Consumer Legislation Amendment Act 2026 (Vic), No. 36 of 2026 — Act as made — Parliament of Victoria (retrieved 27 Sep 2026). Licence: Victorian legislation — free reuse per legislation.vic.gov.au copyright notice
- New changes to property sales and underquoting laws | Consumer Affairs Victoria — Consumer Affairs Victoria (retrieved 27 Sep 2026). Licence: CC BY 4.0
- Industry Q&As: New changes to property sales and underquoting laws | Consumer Affairs Victoria — Consumer Affairs Victoria (retrieved 27 Sep 2026). Licence: CC BY 4.0
Figures on this page are drawn from Delora's local knowledge graph, refreshed from these primary sources and checked for changes on a regular schedule. If a figure here looks out of date, the official source above is always the authority — please let us know.
Evidence record
Keep reading
- Private-sale offers and conditions On Sale process
- Before-auction due diligence On Sale process
- Make an offer Next step