The useful time to decide what would make you reject a property is before the campaign applies pressure.
Write down the fixed requirements, the material risks that must be resolved, the comparable-sales range, the price ceiling and the facts that would justify changing any of them.
A lower price does not repair every compromise. Road exposure, poor natural light, unusable land or the wrong layout may remain long after the negotiation is forgotten. An unresolved title, building, strata, planning, insurance or finance issue may also change the price, terms or decision.
Walking away does not prove the property is bad or another buyer overpaid. It means the purchase no longer makes sense for this buyer on the available evidence.