Soldato
And there's your problem
I would not be buying refurb mobile devices (unless from the likes of network shops) from gumtree, ebay etc.? Especially one X devices given all the faults it has/had.
From a shop who have a no quibble 60 day guarantee, if faulty within that period they will replace/ refund so hopefully any fault will show within that time which in my case it has, also HTC still honour the remainder based on serial number unlike Samsung!