It's no surprise that it costs more to live downtown than it does to live in the suburbs. A new Zillow study highlights just how much of a disparity there is, looking at where the prices spike the most for proximity to the city.

Washington Post writer Michele Lerner reports that in 29 of the 33 largest metro markets analyzed by Zillow, buyers will pay more per square foot for a home within a 15-minute rush-hour drive to the downtown core. In Boston, the city with the most expensive downtown core, the median home in the city is valued at 303% more per square foot than a typical outlying home. Washington came in second with a 218% premium.

The same trend is seen for renters, although the disparity between rents for close-in tenants vs. those farther out is less extreme. Washington has the highest difference in rents, with units within a 15-minute rush-hour commute of the downtown core costing 140 percent more per square foot than rentals farther away. San Francisco came in second with a 139.7 percent premium for closer rentals, followed by Seattle at 91 percent.

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