They'll charge you an hour for diagnosing it I bet, so you'll still pay £120, but you'll save £300 in total.
Ouch. You think?
They'll have a minimum charge, it might be 0.5 hr labour, but could be 1 hr.
@Sparky started
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They'll charge you an hour for diagnosing it I bet, so you'll still pay £120, but you'll save £300 in total.