O - Over-value
Over-value - If a salesman is keen to close a deal on a new car, he may choose to make an offer for your part-exchange which is higher than the true value, rather than discount the cost of the new car.
In comparing any deals, the cost to change is the most important figure. Always try to get a discount on the new car as well as a good price for your part-ex. (See also Cost to change.)