Used car prices vary according to demand. When dealers have a good stock of cars that have been traded in against new models you might expect used car prices to fall.
The prices of used cars is generally at a maximum at the same time as the prices of new cars, at the beginning of the year or of any new, date specific registration period. This is because demand is at a maximum at the same time as supply is maximized.
Used car prices are subject to much bigger variations …