The money you spent on inspections is already gone
Every dollar you spend on building reports, pest inspections, and contract reviews before making an offer is gone whether you win the property or not. Yet those dollars are the reason thousands of Australian buyers stretch past their budget, waive conditions they should keep, and ignore red flags in the very reports they paid for. This step names the trap, puts numbers on it, and gives you the habits to neutralise it.
Of the buyers who were hit by surprise costs:
- 18% went more than $50,000 over their intended budget on a $500,000 purchase .
- 14% had zero savings remaining after settlement .
- 32% had less than $10,000 remaining after settlement .
Once you have paid $1,200 on building and pest inspections and a contract review, the pressure to "justify" that spend by stretching your offer becomes intense. That is the trap in a single sentence.
A sunk cost is gone the moment you pay it
A is money you have already spent and cannot recover. The fallacy happens when you let that spent money influence your next decision, even though it should not.
Arkes and Blumer's landmark 1985 study showed that people who have already invested money in something will keep investing even when walking away is the rational choice . Kahneman and Tversky's explains why — their research showed losing something feels roughly twice as painful as gaining the same thing feels good . When you have spent $1,200 on building inspections and a contract review, walking away feels like a loss. Your brain treats that $1,200 as something you might still "save" by winning the property, even though it is already gone.
Genesove and Mayer found this exact pattern in housing markets. Homeowners facing a loss relative to what they paid set asking prices 25-35% higher than market value to avoid realising the loss . The same psychology works on buyers. Once you have invested in for a property, your brain reframes the decision from "should I buy this property at this price?" to "should I waste the money I have already spent?" That reframing is the trap.
What Australian buyers actually spend before making an offer
Before you bid, you will typically spend money on some or all of the following.
Cost | Typical range | Notes |
|---|---|---|
Building inspection | $350-$800 | Varies by property size and location |
Pest inspection | $100-$250 | Often bundled with building inspection |
Combined building and pest | $450-$900 | More cost-effective than separate inspections |
Contract review (conveyancer/solicitor) | $100-$500 | Some charge a flat fee for pre-purchase review |
(apartments/units) | $300-$500 | Required for strata-titled properties |
For a house, a typical pre-purchase spend is $500-$1,300. For an apartment, add the and you are looking at $800-$1,800. These costs add up across properties. Miss out on two before securing a third and you may have spent $1,500-$3,600 on alone, none of it recoverable.
Three ways sunk costs push you to overbid
The shows up in property buying in three specific ways.
1. Stretching your price ceiling. You have spent $1,200 on inspections and a contract review. Bidding stops at $15,000 above your maximum. You tell yourself that walking away "wastes" the $1,200, so you bid $15,000 over budget. You have now turned a $1,200 into a $16,200 problem.
2. Waiving conditions you should keep. An agent tells you the seller has another offer without conditions. You have already paid for inspections and feel confident, so you drop your finance condition to compete. If your loan falls through, you could lose your full deposit, typically $50,000-$80,000 on a median-priced home.
3. Ignoring red flags in reports. Your building inspection reveals $8,000 in necessary repairs. Rather than renegotiating or walking away, you press ahead because you have already "invested" in this property. The $8,000 repair bill does not care how much you spent on the report that found it.
Five habits that neutralise sunk cost thinking
1. Set your maximum before you spend anything. Write down your absolute ceiling price before you pay for inspections. When the number is set in advance, it is harder for sunk costs to shift it .
2. Budget for due diligence as a separate line item. Treat inspection and legal costs as a recurring expense across your property search, not an investment in a specific property. Budget $2,000-$4,000 for your total search, spread across however many properties you pursue.
3. Use the "fresh eyes" test. Before making a final decision, ask yourself: "If I had not spent anything on this property yet, would I still pay this price?" If the answer is no, the sunk costs are doing the talking.
4. Talk to someone who has no money in the game. A friend, family member, or financial adviser who has not spent weeks researching this property will see the numbers more clearly than you can.
5. Remember the maths. Walking away from $1,200 is painful. Overpaying by $20,000 on a 30-year mortgage at 6% costs you roughly $43,000 in total repayments [8]. The is always the smaller number.