Austin-Round Rock, Tex.

Share of income used for rent: 18.2%
Average rent: $870
Median household income: $57,262
12-month increase in rent: 4.2%
Population: 1.67 million

Austin, famous for its vibrant rock music scene, is home to the University of Texas and a strong high-tech sector. Rents aren't as low as they are in other parts of the state, but salaries in the Austin area tend to be relatively high. The area's asking rents for apartments jumped 4.2% in the fourth quarter, compared to a year earlier. The apartment vacancy rate was 7.5% at the end of last year.