Charlie Gardner has written a fascinating post about Brownsville and Matamoros, two cities separated by the Texas/Mexico border. The essay is mostly a contrast between their different urban-planning styles: Lot sizes are smaller in Matamoros, Mexico, for example, and "Single-use zoning seems to be unknown or unenforced, as numerous small commercial establishments can be seen cropping up, mid block, along these [residential] streets." Among the results:
although Brownsville is very cheap by American standards, with a median home price of $130,000 for what is typically a three bedroom home, a relatively large Matamoros starter home (915 square feet over two stories on an 1130 square foot lot) can be had for only $34,000. The tiniest of the starter homes, no bigger than a studio or micro-apartment, are as little as $10-15,000. This suggests that a new two-bedroom home in Matamoros can be purchased for approximately what the down payment would be for a typical three bedroom home in Brownsville, and helps explain Mexico's very high homeownership rate. Finally, it has implications for mixing of uses, since the dense packing of houses allows for businesses to thrive on foot traffic, reducing the political pressure for parking minimums that would, even in the absence of zoning, effectively ban businesses on tiny lots.
The towns are similar in many other ways: geography, demography, even wealth. (Brownsville is poor by U.S. standards, and Matamoros is relatively rich for Mexico: According to Gardner, the former has a GDP of $14,000 while the latter is just below that at $10,000.) Of course there are important differences as well, but it's still sort of a natural experiment in diverging urban ideas. Read the whole thing.