Apple lowers maximum iPhone trade-in values, best deals now limited to trade-ins with purchase

Juli Clover:

Apple used to offer a maximum of $500 when doing a direct iPhone trade-in through its trade-in website, and just a few weeks ago, we tested trading in an iPhone X and were offered $500 by Apple. Today, Apple’s maximum price for the same iPhone X is $349.

And:

That same iPhone X that’s worth $349 when doing a direct trade-in with Apple is worth $450 if you trade it in while buying a new iPhone XR.

Wondering if there is a reliable web site that tracks best trade-in price for a particular iPhone model at the various trade-in web sites, including Apple.