Is it worth buying 2 month old iphone x 256 gb for £560. Apple replacement bcoz of warranty. As new, he got it on Feb 2019?

Is it worth buying 2 month old iphone x 256 gb for £560. Apple replacement bcoz of warranty. As new, he got it on Feb 2019?

No.

As they sell for far more than that secondhand you have to ask why someone is effectively giving you a subsidy of hundreds of dollars.

One common scam is to sell cheaply and then report the phone lost or stolen to an insurer so that the thief gets a new phone and yours gets permanently blocked.