You're making the classic mistake of confusing supply and demand with quantities supplied and demanded. Demand changes because of peoples tastes and desires, quantity demanded changes because of price. The supply of materials (and their corresponding price) will have no effect on the demand for big homes.
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She was standin' alone over by the juke box, like she'd something to sell.
I said "baby, what's the goin' price?" She told me to go to hell.

Bon Scott - Shot Down in Flames