Duchy Originals is clearly a commercial enterprise, he collects rent on properties, makes profits when he sells trees…
The Duchy Originals label was sold to Waitrose when it stopped turning Charles a dime.
Charles collects rent on properties, yes. Including Highgrove, owned by the Duchy of Cornwall and thus recycling his own rent payments back to himself in the form of Duchy profits. Willy is now his landlord...
The tree thing was another triumphal sleight of hand. He claimed he owned the things which were growing on Duchy land then sold them back to the Duchy earning himself a couple of million in the process.
Claiming it's all above board 'cos tax is laughable.