Ask the driver how the auto box feels when pulling away. If you can also get him to try reverse too. If you stand by the car while it's in line and before it goes through the block you'll get time. I try and go the day before auction and blag the keys from the key office. then although you'll be hemmed in by other cars at least you can crawl all over it, dip the oil/check fluids etc, look at the service book, and generally get a good feel for the car.