Sam is considering buying Robert's property, which has a house and 5 acres of land. Robert is very keen to sell the property and tells Sam that if he buys it, Robert will leave all the gardening equipment in the shed of the property including a ride on over valued at about $10,000. Sam is happy with this and a contract is drawn up and both Robert and Sam sign it. There is no mention of the gardening equipment in the written and signed contract. When Sam moves in to the property he realises Robert did not leave the gardening equipment as agreed. Robert says he is not obliged to as it was not in the written contract. Sam says it is a collateral warranty, which forms a collateral contract. Advise Sam.