As a self employed instructor I think you would be OK as long as you then offset these costs against earnings from this type of instructing, you can show this as a loss in your accounts for this area and would be able to put this loss against your overall profit, but if you did not show you had used the ratings once gained you could be on shaky ground. Please note though, I am
not a tax accountant so this is only an opinion from someone in the business.
