The garage I used to work for had an arangement with the test station that performed all of the testing. We were billed for the full retail price on each test. (monthly account). We were also re-ebursed a set amount for each test. The wording was something like "disbursement for MOT's" Putting it simply a credit was raised for each test, that brought the cost down to the trade rate. From what I remeber, each credit was not subject to VAT.

HTH

Dave Hill