By Jodi Summers

No one’s arguing that the heady years of double-digit property appreciation have come to an end, but just how far prices may drop seems to be somewhat less certain.

Nationally, residential real estate sales dropped by about 9 percent in 2006 to 6.5 million units sold down from around 7.1 million units in 2005, according to National Association of Realtor statistics. During 2006, inventories rose about 36 percent — 3.8 million units were available for sale versus 2.8 million units at the end of 2005. National price increases were an estimated 1.9 percent for all of 2006.

NAR predicts that existing single family sales will drop to 6.4 million units in 2007. Price growth will stay relatively flat — total price increase is predicted to be 1.7 percent in 2007.

“The boom is definitely over, there’s no debate about that,” said Mark Zandi, chief economist of research firm Moody’s Economy.com. “It has been correcting for about a year, and it’s got another year to go.”

“It is a question of whether it is deep and quick or not so deep and much longer,” observes Edward Leamer, director of the UCLA Anderson Forecast. His thoughts is that the current lull in the market will be, “Not so deep and rather long.”

Leslie Appleton-Young, vice president and chief economist of the California Association of Realtors notes that in 2006, sales of the state’s homes dropped 23 percent from 2005. “We think home sales in California will drop another 7 percent this year. We think we’ll see about a 2 percent decline in the state median price, particularly in the inland part of the state.”

In Los Angeles County, reports DataQuick, median home prices rose 2.6 percent to $510,000 as sales fell 18.9 percent. Nice growth in San Bernardino County which saw a median price rise of 8.6 percent to a record $380,000, while sales declined 26.7 percent. Riverside County saw the median price rise 5.2 percent to a record high of $426,000, with sales down 35.7 percent from a year ago. San Diego County saw a median price drop of 6.9 percent to $482,000, as sales fell 24 percent. Ventura County lost big as housing prices falling 8.2 percent to $562,000 with sales sliding 30.8 percent. Orange County property saw no appreciation — the median residential property price of $616,000 is the same as 2005. Sales dipped 29.3 percent.

If real estate varies this much county to county, can you imagine how much it must vary from region to region. What happens in Miami, Fla., may be completely different from what is taking place in Pittsburgh or Albuquerque. Not everyone benefited equally from the boom, and not everyone will suffer the same in a bust.

Areas that were once centers of the boom — Phoenix, San Diego and Las Vegas — will be among the hardest hit observes Leamer. “Regions where a lot of the economic growth came directly from the real estate sector and where that was a huge plus, that’s going to turn into a huge negative,” he explained. “Wherever the party was the loudest, that’s where the hangover is going to be the greatest."

To get a sense of how home prices will perform in various parts of the U.S., Forbes asked Moody’s Economy.com to forecast historic and predicted median home prices in 15 major metropolitan areas. The company bases its forecasts on an econometric model that looks at the relationship between prices and various factors that have historically driven supply and demand in these markets.

They looked back 10 years and forward another 10. The results indicate that several cities — such as Boston, New York and Washington, D.C., — should experience downs and ups in coming years. Places, such as Houston and Minneapolis-St. Paul, will just keep marching along.

Jodi Summers negotiates investment properties for Sotheby’s International Realty.

Contact her at jodis@verizon.net or (310) 260-8269. Visit her Web sites at www.SoCalInvestmentRealEstate.com or www.santamonicalandmarks.com.