Systems and methods are provided for periodically calculating a guaranteed price for a used durable good, such as an automobile. The current guaranteed price is continuously accessible by an owner of the used durable good for an extended period, and the owner can receive at least the value of the guaranteed price at the owner's discretion. A guarantor of the calculated guaranteed price backs a transaction that ensures that the owner receives at least the value of the current guaranteed price in exchange for the used durable good. The transaction may include a trade-in of the used durable good.