Hi, I have sold my 15yr old car recently. Before the person came to inspect the vehicle, I told him that the car has a transmission issue and he was still happy to proceed. The next day he came for inspection and test drive. I told him my ownership history and any problems I know of, that are related to the car. I also indicated that some parts have been modified. The person inspected the vehicle, took it for a test drive and was still happy to purchase it. The next day I drove the car 35Kms to his place to drop it off and complete the sale, all the gears were working. Once I dropped off the car, I went on my way home. The same day about 6 hours later, he called and said that the reverse gear doesn't work and the car rolls. He said that he needed some money for the repairs and requested $700. I gave him the 700. About a day later he calls back saying that there is too much repairs and he wants his money back. He is continuing to call and argue with me. I stopped picking up his calls as I feel nervous and a little bit scared. The car is no longer under my name, and he was still happy to purchase the car even though I told him about the problems. Am I entitled to give his money back under Australian Consumer Law? And what do I do if he shows up at my address?