I've been charged £480 repair for a £350 phone by HTC - anyone else?

[AC Question]

Has anyone else had dodgy dealings with HTC repairs under warranty? My M8 was charging slowly (everything else was perfect) so sent it in for repair - and they claimed 'water damage' (it's been in a water-resistant casing with tempered glass screen protector from the day I got it) and want £480 for repair! A brand new M8 costs £350! I'm guessing a scam..anyone else had this problem? My phone was perfect apart from charging being slow...that's not £480-worth of 'water damage'.