Harry and Sally make an offer to buy a house in NSW. The agent tells them they should exchange immediately because George, who is parking his car outside, is also interested. Harry tells Sally that they should go ahead, even if they don't have their finance approved, because they can easily withdraw from the contract. They immediately exchange contracts. George is angry about this and tells the agent he was prepared to offer $20,000 more than Harry and Sally. The vendor hears about George's counter offer and instructs the agent to cancel the contract with Harry and Sally.

You should reference applicable sections/points of the Conveyancing Act 1919, to outline the respective legal rights of all parties.