REVIEWS AND APPEALS
If you do not agree with a Customs decision - either concerning an import entry or BTI - you can request a Review. You can do this yourself, in which case you need to be careful as you might miss some of the possible arguments. But Customs will explain their review decision to either uphold or overturn the original decision. About 25% are overturned, so it is by no means a waste of time. They might be in the same Department but they are truly independent.
As with anything, do not seek a Review lightly as we do not want to swamp the Review Team, which is not large. This helps get quicker Consideration for those cases that matter. I can advise whether it is worth seeking a Review, and if you wish progress the Review for you. If I think that the decision is wrong, I can assemble all the arguments for the next stage.
If the Review Team upholds the original Customs decision then you can appeal to the independent VAT and Duties Tribunal. Customs use good lawyers, so you good grounds. I can advise on whether your case has a chance. There is no point fighting clear law. You do not have to appoint expensive lawyers unless you can afford it. You can keep costs down by presenting the case yourself. I can do so on your behalf, and will be better at it than you, but possibly not as good as a lawyer (in presentation, though I fancy I will be better at classification!). My costs would naturally be lower. It is a balance of the strength of case, your pocket, and the revenue implications.