How can I identify the age of a vehicle?

The registration plate is a good place to start. Cars made after 2001 have the AA11 BBB format, with AA indicating the place it was registered, 11 indicating the year, and BBB as an identifier to distinguish it from other cars. The way numbering works is if the car was made between February and September, the first digit will be the third digit of the year, if not it is the third number in the year +5. The second number in a registration plate is the fourth (last) number in the year. For example a car registered in January 2006 would have the numbers 56, but a car registered in August 2011 would have the numbers 11.