Trading in multiple devices for a single item purchase
I have recently come into possession of a bunch of devices through my father's estate for which I'm the executor. I would like to trade them in and get a credit towards the purchase of a new device.
I've got 3 devices and I want to trade them in and get a credit towards the purchase of a new MacBook Pro for myself.
I've never done a trade-in before so I don't know the protocols and I need some advice for what's the best way to accomplish this. Should I go in-store with the products in hand? Try to get a gift card / multiple gift cards? Does Apple require proof of ownership? I'm not sure what to do if they were purchased through a reseller.
There's a 4th item (iPad - year unknown) which I think my dad won in a raffle - it doesn't seem to allow me to log in even after a factory reset, no idea what to do with that, seems like it's partially bricked.
tl;dr multiple items I have come into legal possession of and I want to trade them for a purchase for myself.