The Wilson Quarterly (WQ, Summer 2008, Vol. 32, No. 3) published an article by Witold Rybczynski about affordable homes:
What's driving the high cost of houses today is not increased construction costs or higher profits...but the cost of serviced land.
The author refers to "serviced land" in two ways: one, the passing of costs from the government to developers for infrastructure; and two, NIMBY (Not In My BackYard).
Prior to Prop 13, the government would increase taxes on local communities for services necessary to increased population growth, such as new roads, new parks, sewers, and general maintenance. Now, many local governments cannot increase property taxes to make up for the increased need for services, so they force developers to pay these costs if they want to build. The developers take the financial infrastructure hit up front and pass those costs onto the homebuyer at the end, in the form of higher home prices.
NIMBY is easy to understand in this case. There is "widespread resistance to growth," so locals pass zoning laws and restrict building permits to prevent more houses from being built. These legally mandated slow growth policies lead to pent-up demand and not enough supply of houses, causing artificially inflated values. Anyone who's lived in Northern California and New York knows there isn't really a problem with overpopulation and population density in California to justify California's slow growth policies--at least not yet.
According to the research of economists Edward Glaeser of Harvard and Joseph Gyourko of the Wharton School, since 1970 the difficulty of getting regulatory approval to build new homes is the chief cause of increases in new house prices. In other words, while demand for houses has been growing, the number of new houses that can actually be built has been shrinking.
One tactic cities use to stall new homes is zoning for large lots, like one acre. This forces larger houses and higher prices. In the past, many individual homes would be only 1/6 of an acre. The author states:
Smaller houses on smaller lots are the logical solution to the problem of affordability, yet density - and less affluent neighbors - are precisely what most communities fear most.
I would love to see a return to smaller houses. One advantage of not having a lot of space is people will consume less if they know there isn't so much space to hold their new purchases.