Try some of the big Cardiff/Newport hauliers. Many do their own driving school. You may be tied to the haulier for a couple of years but if it saves you the upfront cost it might be a price worth paying. Last time I was out that way I seem to remember an urban with L plates on it in the Owens yard at Newport.
As for extra cost, I did my class 1 for an extra 950 seven years ago.
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