Over time, the rowhouses expanded, and we added the twin to our housing stock, but the result of more homes and high ownership continued. This model of affordable comfort in housing, combined with a history of lower-than-average real estate taxes, powers Philadelphia's middle class and working poor. Yet more and more public officials and thought leaders have voiced concern that this legacy is in danger, citing rapid increases in sale prices in the neighborhoods closest to Center City as proof. In Graduate Hospital and Point Breeze, blocks where homes had once sold for $50,000 now have neighbors who may have paid more than $500,000. As Philadelphia's economy begins to grow after a long period of stagnation, more neighborhoods will begin to see demand increase for housing, especially those closest to Center City and other major amenities.