I booked a child seat through the rental company, but when I arrived at Melbourne Airport, the rental counter said I hadn't reserved it in advance and they didn't have any available on the spot. They told me I had to find a child seat myself before my 2-year-old son could get in the car! I made countless phone calls and searched all over the airport and nearby areas, but couldn't find any child seat rentals or sales. Talking to the rental company's representative over the phone didn't help either. Eventually, the rental company told me to come back the next morning to pick up the car, maybe they would have a child seat, but only 50% chance, and they couldn't guarantee it. Fortunately, the rental company called me later in the evening to inform me that a child seat was available.