America's Most Expensive ZIP Codes (2010 Edition)

The value of a home is based on the basic economic principle of Supply and Demand. When the number of buyers exceeds the number of sellers, home prices rise. Conversely, when sellers outnumber buyers, home prices fall.

There's always a opening price point for negotiation and that figure often factors in specifics like square footage, number of rooms, and finishes and amenities. Location matters, too.

On a ZIP code-by-ZIP code basis, prices can vary wildly and it's tiny, tony 91008 -- located in Duarte, California -- that tops the 2010 Forbes list of America's Most Expensive ZIP Codes. Home to fewer than 1,400 residents of Los Angeles County, the ZIP code's median home cost is $4,276,462.

By contrast, the median home cost across all of Duarte's ZIP codes is just $358,454.

As listed by Forbes, America's 10 most expensive ZIP codes are:

1. Duarte, CA (91008) : $4,276,462
2. Atherton, CA (94027) : $4,010,200
3. Rolling Hills, CA (92074) : $3,892,456
4. Alpine, NJ (07620) : $3,814,885
5. New York, NY (10014) : $3,785,445
6. Beverly Hills, CA (90210) : $3,684,150
7. New York, NY (10065) : $3,626,001
8. Belvedere (94920) : $3,283,269
9. New York, NY (10012) : $3,221,371
10. Santa Barbara (93108) : $3,151,220

The real estate market is a local one, as evidenced by the Forbes list. Even within large cities like New York, there are areas that stand out from the pack in terms of cost and affordability and the same is true for all cities.

Therefore, when you need local market data , look past the "national statistics".  Talk to a real estate agent with local market knowledge instead. It's the most reliable way to get data that matters.