Apple has now opened its trade-in program for the iPhone 13 series. In typical Apple fashion, the company's own flagships are by far the most valuable, with the iPhone 12 Pro Max being worth almost twice as much as the most valuable device from any other manufacturer.
https://www.notebookcheck.net/Apple-s-iPhone-13-series-trade-in-program-throws-up-a-few-surprises.562212.0.html