After I did my CPL(A) and instructor rating, submitted my first tax return as a self-employed sole-trader, tried to claim the costs of the training courses and tests to offset against income tax. Was summoned to the local tax office and told that the initial cost of obtaining a qualification couldn't be claimed, but once you had it, anything to keep it valid was acceptable. Can't see them making any difference between fixed wing and rotary. Seems like setting up a company is a better way to do it.