if the price is the same I dont see how it will work. If you are really going to pay for a ball in advance that you expect to be available for your use when you arrive at sunset then you should be prepared to pay a premium for it. If each bay will have a bay manager that will police the mooring for the paying customer and all these balls will be new for the purpose then why wouldn't you charge more... my guess is that this will flare out. First come first served is just fine. Anchoring for the latecomers is also just fine... and its free!