On the point of cost of housing, I believe the author's intent is that, if we built new places as he describes, they needn't cost any more than current suburbs.

On the point of cost of housing, I believe the author's intent is that, if we built new places as he describes, they needn't cost any more than current suburbs. To add my own point, I am sure that house prices in San Francisco are high because of high demand and limited supply, not because they are intrinsically more expensive to create.