I've read some pretty horrifying stories about Apple (this person had a cracked screen, Apple bricked the phone while attempting to repair it, replaced it behind his back, then charged him 3x -- they also have a required replacement device "security deposit" you must pay up front in order to even get them to attempt a repair):

https://www.aaron-gustafson.com/notebook/apple-support-honey...

There's a reason why third-party repair shops like Rossmann Group exist and make a killing doing component and board level repairs on iDevices.