If I bought a water-damaged secondhand iPhone - one that I had never used myself - would it be eligible for an out-of-warranty replacement? (In other words, could I legitimately replace it at the Apple Store for a fee)?
As long as the phone has not been opened by unauthorized service provider or the last owner, you can show a proof of purchase, and it is eligible according to the Repair Terms and Conditions, Apple might do that.
Out-of-warranty repair service
If your repair isn’t covered by Apple’s One Year Limited Warranty, AppleCare+, or AppleCare Protection Plan, your iPhone might be eligible for out-of-warranty service. For example, liquid damage isn’t covered by warranty but might be eligible for out-of-warranty service. Some damage isn’t eligible at all, for example if your device has been broken into multiple pieces. See Apple’s Repair Terms and Conditions for complete details.
Read Apple’s Repair Terms and Conditions
Model Out-of-warranty service fee Battery service* iPhone 6s Plus, iPhone 6 Plus $329 $79
*available only if battery
fails Apple’s diagnostic testiPhone 6s, iPhone 6 $299 iPhone 5s, iPhone 5c, iPhone 5 $269 iPhone 4s $199 iPhone 4, iPhone 3GS, iPhone 3G $149 Plus a $6.95 shipping fee, if required. Fees are in USD and exclude local tax. Pricing is for service through Apple. The final service fee we charge will be determined during testing and may be less than the service fee listed above. Pricing and terms vary for service through an Apple Authorized Service Provider.
Out-of-warranty pricing varies for Apple accessories such as adapters and Apple iPhone cases. Contact your carrier, Apple, or an Apple Authorized Service Provider for more information.
copied from Service Answer Center - iPhone
Thank you. When you say proof or purchase, do you mean relating to the original purchase of the product (when it was brand new); or simply something to show that the phone has been purchased by me (e.g. an ebay confirmation)?
Does the fact that the phone has no association with my iCloud account matter? Or that it might be associated with the previous owner's account?
Assuming that a replacement would be given, this seems like a very easy way to acquire a new iPhone at a markedly lower cost - too good to be true?
The Activation Lock has to be deactivated before you can get the phone serviced or replaced. So, knowing the Apple ID and password that has been used to set up the phone, or getting the Activation Lock disabled by the previous owner would be essential.
this seems like a very easy way to acquire a new iPhone at a markedly lower cost - too good to be true?
You don't get a new phone. you get a refurbished phone. New case, screen, and battery. The value of your "new" phone will be same as what you purchased so you have not gained anything in the process.
As to whether Apple will do this for the second owner is Apple's decision and you would have to deal with Apple directly (this is not Apple on this board).
Out of warranty replacement for a phone bought secondhand.
