If your getting it at a retail store, its gonna be 249.99, however beware of Toys R Us, there is a lot going around that they force you to buy it with a game, the one included doesnt count.
My tip is don't drink any fluids if your gonna be camping out. I had fun watching people trying to hold it in.
You won't need to camp more than one night, probably not even have too. It depends on your area, since you live in a large city, maybe 2 or 3?