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Think they all have at least two, most have quite a few. However when the booking office is closed, there will only be one or two in the concourse or on the platforms, such as York or Darlington.
Think Inverness too has a sole/lonely machine - right in the middle of the concourse.
Fortunately it was working to collect TOD (via Southern for RainyDayGuarantee as it then was) when I was up there on an EC First £25 London-Inverness fare earlier this year.