Why are famous paintings worth more than famous houses?
David Galbraith calculates that if buildings by famous architects were priced like paintings, a Le Corbusier building would be worth more than the entire US GDP.
The top floor of Corbusier's Villa Stein (one of perhaps the top 500 most important houses of the late 19th/early 20th centuries - i.e. a Van Gogh of houses) is for sale for the same price per sq.ft. (approx $1400) as buildings in the same area of suburban Paris, designed by nobody in particular. Meanwhile, Van Gogh's Portrait of Dr. Gachet sold for an inflation adjusted price of $136 million yet a poster of similar square footage and style costs around $10.
In terms of signaling, it's difficult to hang a house on one's parlor wall...buying a Corbusier means living in it wherever it happens to be located, at least part of the year.