Cutting your costs
You want to make sure you like where you stay plus I would not want to move mid stay - eats up valuable beach time!

Do you need a car? - maybe not if staying in Orient Village
but we also always take a cab [Wilfred Brooks] our 1st and last day even when renting a car
If you want a car, then maybe location becomes more flexible. Oyster Pnd for example has several reasonable places to stay - you'll have to drive to beach it, but if a car is mandatory for you, then an option

Also to me air bnb is not always the least cost place to look

J&B