"Thank you, that will be fifteen pounds ninety."
We had walked across the cliffs, round Bolt Head and down to South Sands, under a cloudless sky, through the smells of coconutty flowering gorse and sweet-pungent wild garlic, often pausing to let my legs and lungs catch up, and for us to gaze down at coves that can't be reached except by sea, but were now displaying rarely seen expanses of yellow-ochre sand sloping down to shallow turquoise sea.
"It's the lowest tide of the year," announced the Tidal Bore, having consulted his iPhone. "Plus 0.2. Extraordinary."
"Put that thing away," said Mrs TB.
Along the way, I learnt a lot about harbour dues. These are fees you have to pay in order to be allowed to moor or launch a vessel at a given coastal location. This is (I think - I don't always keep up with my brother on points of detail) on top of any rental you may have paid in order to park your boat. Fair enough - there are costs to be covered. But I raised several eyebrows at the information that you're meant to pay harbour dues to launch a kayak.
"It's not much, only about £10 a year."
"Even so," I said. "And, what about casual visitors, tourists who just turn up with their kayaks or whatever?"
We descended to South Sands, our destination, and entered the bar of the swish new South Sands Hotel for a well-earned freshener. My round.
"Two pints of Doombar, please," I instructed the barman. "And a glass of red wine."
"Thank you." He manipulated his till and smiled. "That'll be fifteen pounds ninety, please."
I have now mapped out my new career path. When the caravan season opens, in a couple of weeks' time, I will acquire a comfortable folding chair, a peaked cap, a book of cloakroom tickets and a clipboard. I will spend my days sitting on the beach at Wisemans Bridge, and when an SUV turns up towing a jet-ski or a brace of kayaks, I will look up and smile.
"Harbour dues, please," I will say.
"Oh, er, all right. How much?"
I will consult my clipboard.
"That will be fifteen pounds ninety, please."