Apple now offer a trade-in service on current Apple devices such a Phones, Watches, iMacs and Macbook's It's called “Apple GiveBack”.
https://www.apple.com/au/trade-in/
Turn the device you have into the one you want.
Trade in your eligible device and you could receive an Apple Store Gift Card.
Apple are offering up to $700 on newer devices.
If not, you can always bring it to us for an upgrade and keep it going for a few more years yet.
:jk: