As the old saying goes, you get what you pay for. Unfortunately in real estate, value is a trade-off. Someone in Manhattan is willing to pay $2,200 per month to rent a studio apartment so as to be near jobs and cultural amenities, sacrificing square footage. For someone in Las Vegas, where housing is inexpensive—the city's median home value is about $115,000, according to real estate site Zillow.com—and the labor market is tough, the reverse is true. What if you could have both proximity to work and quality of life at an affordable cost?

While this may sound too good to be true, it's the status quo in some places. In an exclusive ranking for Businessweek.com, Bloomberg Rankings analyzed government-gathered data on more than 3,000 counties across the U.S. to select the best affordable place in each state. We then scored each county by state. Next we tallied the top-ranked county in each state to arrive at a national ranking. Factors that were most heavily weighted include housing cost, crime, unemployment, and educational attainment in the county, in addition to such other metrics as family income, poverty, commute time, air quality, diversity, and share of families with children. We considered only counties with median income ranging from 85 percent to 125 percent of their states' median income, with poverty rates below the state rate. State-level student-teacher ratios and state SAT scores were also considered to gauge education values within states.

"We looked for diverse populations with robust economies where people could live and work," says Jennifer Prince, rankings analyst for Bloomberg.

The Midwest made out well in the ranking. No. 1 on Bloomberg's list: North Dakota's Cass County, home to Fargo and West Fargo. Other areas with high scores include Brown County, S.D., Cleveland County, Okla. (in the West South Central region), Story County, Iowa, and Olmsted County, Minn.

Coastal states with high unemployment such as California, Florida, and Rhode Island ranked lower, as did states with a generally high cost of living, such as Hawaii.

Cass County's Low Cost of living

Cass County Administrator Bonnie Johnson says affordability and a strong economy have attracted many. North Dakota's fastest growing county, Cass's population swelled by 21.6 percent over the last decade, to 149,778 people, according to 2010 U.S. Census data. Most of the population lives in Fargo, which grew by 16.5 percent, yet Johnson says the fastest growing area is West Fargo, a smaller city that experienced a 72.9 percent increase in population since 2000.

Demand for housing has grown with the population, yet prices remain low because residential stock increased. The median list price in the county was $159,000 in April, according to Zillow.com. The median property tax paid on homes is $2,651, about 3.73 percent of median household income, according to 2005-to-2009 data from the Tax Foundation, a Washington-based think tank that promotes lower taxes. (The U.S. median is 2.81 percent of income.)

With expenditures so low, only 23.6 percent of Cass County households spent more than 30 percent of income on housing (considered by housing authorities to be the threshold for affordability)—far below the national rate of 36.7 percent revealed in U.S. Census Bureau figures.

In Brown, Cleveland, Story, and Olmsted counties, the share of households spending more than 30 percent of income on housing also ranged from 20 percent to 25 percent, data show.

Job Opportunities a Big Lure

Housing is a major factor in making a place affordable—and attractive. According to recently released results from the Census Bureau's 2010 Current Population Survey, housing is the main reason people relocate: Of people who moved in 2010, 43.7 percent did so for such housing-related reasons as finding a new or better home, cheaper housing, or a neighborhood with less crime.

That's just part of the picture. "People follow jobs and not low-cost housing," says Lawrence Yun, chief economist and senior vice-president of research at the National Association of Realtors. "North Dakota has been doing well because of job growth while Las Vegas and Cleveland continue to struggle—all [are] very affordable markets," he says.

About 16.4 percent of people in the U.S. who moved in 2010 did so for employment-related reasons, says the Census Bureau's survey.

The labor landscape in Cass County is strong, accounting for just over one-fourth of total employment in North Dakota, according to U.S. Bureau of Labor Statistics Regional Commissioner Charlene Peiffer. The county's unemployment rate has stayed below 5 percent through the downturn and stood at 4.1 percent in March, estimates the BLS. (The state's unemployment rate was even lower, at 3.6 percent, that month.) According to the U.S.Bureau of Economic Analysis, the fastest growing sectors in Cass County since 2001 include company management; professional, scientific, and technical services; and education.

The jobless rates in the four other counties atop the rankings were also below 6 percent in March, according to the BLS.

Retirees Chase Low Prices

"The one group who would move for cost advantage would be the people who do not need to work—namely, the retirees," Yun says. When Florida became expensive during the boom, retirees searched in the Carolinas, he adds. After the housing bust, Florida and Arizona "may now look quite attractive for retirees again."

Even in these best affordable places, it's wise not to expect Utopia. In Cass County, for example, flooding is common in the Red River Valley. This year, the river crested in the Fargo area at 38.75 feet in April, according to the National Weather Service, making it the fourth-highest flood on record. It has since declined slowly.

Still, when it's not flood season, Cass County can be an attractive place to live. Unlike many places with nice homes, clean air, low crime, and a strong job market, it's accessible to the average income earner, too.

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