Online tools can help gauge the trade-offs. To get an idea of how local incomes compare, enter a query in Bankrate's cost of living comparison calculator, which compares the income required to maintain your current standard of living in two different cities.

The contrasts can be stark. If you were earning $80,000 in Atlanta, you could maintain the same lifestyle on 9.79 percent less, or $72,167, in Knoxville, Tenn., according to the calculator. A New Yorker earning $200,000 could move to Toledo, Ohio, and support the same lifestyle on 52.29 percent less income -- $95,417. A San Franciscan would need $125,000 to enjoy the lifestyle a Salina, Kan., resident could get for $60,523. All these calculations are based on financial considerations and, of course, do not take into account cultural variations.

Seek economic stability
Sometimes real estate is cheap for a reason. That's particularly true in cities with high crime rates, a shrinking job market or underperforming public schools.

Granted, economic turnarounds do occur. And investors adept at spotting blighted areas primed for transformation have done very well. But if you're looking for a place to relocate and live in now, Sperling says it's wiser to stick to locations with stable economies.

Capital cities and university towns tend to be good picks, since they tend to have stable job markets. It's prudent to avoid places where the local economy is dependent on a single private employer or industry. A cyclical downturn in that industry can adversely affect the whole community.

Consider where you have a network: Moving is stressful enough. Going to a new place where you don't have friends or family can make it more difficult. That's why many people looking to relocate from high-cost areas start by looking at places where they already have ties.

That was the case for John and Alane Mastandrea, who moved this year from a New York City suburb to a Cleveland suburb not far from Alane's parents. Affordable housing was a key motive. The Mastandreas, who have two young sons, are buying a four-bedroom house in the college town of Berea, Ohio, for under $200,000.

"In New York, I was too intimidated to even enter the marketplace. The asking prices might as well have been denominated in Monopoly money," John Mastandrea says.

He estimates that a house comparable to the one he's buying in Ohio would be at least three times the price in his old New York neighborhood. For New York friends who also can't afford to buy locally, he advises a course of action similar to his own:

"I tell people to exploit their own special circumstances -- friends or family who live in lower-cost-of-living locales."

Joanna Glasner is a freelance writer based in California.