...of course, he might simply be trying to calculate his max range for cruising.
I was reading an article in that Motorboat mag about a lad who spent £660k on a sportscruiser. He spends about 12k a year in marina fees. He spent about 2k on fuel last year. Fuel economy and two fridges where his main criteria for selecting the craft
Biff's right, fuel is what Mastercard is for.