$300,000!? Wow, Kerplunk you must have some pretty high standards. That is one hell of a down payment!
The thing about this competition argument that is irking me is that for as many different companies there are out there, the product that you are buying at the pump is more or less the same. The only thing that is going to effect the gas price in the way you so desperately want it to is when some company opens up a station in every city that sells X, which can be put in cars to fuel them, but costs half as much to produce. Only then would you see "free market competition" in action. (Well, in that case it would probably be more like all out war, but you get my point).