Inheritance Subtleties?

[Trinithis]

As far as I can tell, the following do exactly the same thing:

function House(location, cost) {
	this.location = location;
	this.cost = cost;
	}

function Mansion(location, cost, size) {
	this.parent = House;
	this.parent(location, cost);
	this.size = size;
	}

function House(location, cost) {
	this.location = location;
	this.cost = cost;
	}

function Mansion(location, cost, size) {
	House.call(this, location, cost);	//Or similarly with apply()
	this.size = size;
	}

Are there any differences whatsoever? If so, which technique is better?

[Twey]

Nope, no differences at all (other than the obvious, that the latter creates a parent property).