Hi,
Interesting point about buying a large amount and asking marina to store it, a diffrent slant might be to purchase an amount of fuel prior to November, then draw down various quantities as and when needed. I have a pal who when he gets paid puts an amount of money on a tab at his local, he then drinks as he pleases, buys rounds what ever until his monthly "credit" is down to nill, if he does the lot in 3 weeks he has a dry few days............it's a thought.