Silicon Valley's housing market took a breather in January, as inventories fattened and prices flattened, but many buyers may have missed the boat. January sales weren't sailing either.

Mortgage interest rates falling for four consecutive weeks has helped steady affordability so far this year, as prices on single-family detached homes rose only $3,000 in January, a respite from nearly a year of price increases that tacked $109,000 onto the median cost homes.

A more detailed look at communities within the greater Santa Clara County area, shows a mixed market where virtually every community yielded fewer sales both month-to-month and year-to-year, with higher end markets more often suffering price declines.

In San Jose, for example, the median price of single family homes rose $10,000 from December to January. Sales fell from December to January but rose from January last year to January 2005.

"The city of San Jose is more of a low-end marketplace and the number of transactions is up almost 10 percent," said Richard Calhoun, broker/owner of Creekside Realty in San Jose.

Calhoun says the current data is seasonal and not very useful in determining any trend. January's data features sales from the traditionally slower holiday season which almost always reveals less activity, if only temporarily.

For consumers, real estate agents say, the uncertain market is compounded by the increased number of green real estate agents who haven't developed the experience necessary to see through current market conditions.

"You really need competent help. The sharper agents are more polished and educated as far as knowing what the market is doing," said Robert Aldana, president of the Hispanic Association of Realtors and Affiliates, who recently conducted a town hall meeting to respond to the rising number of complaints against real estate agents.

Countywide, Calhoun's Bay Area Real Estate Market Newsletter reveals the median price of single-family detached homes in closed sales moved from $555,000 in January 2004, to $661,000 in December 2004 to $664,000 in January 2005--another median price record.

Sales plummeted during the traditional seasonal drop from 1,185 in December to 839 in January this year, compared to 849 a year ago.

Meanwhile, the county's inventory of single-family detached homes plunged from 2,324 a year ago to 1,547 in January this year, but they were up from 1,351 in December, according to Calhoun's report, which is composed of closed sales statistics from the area's official multiple listing service, RE InfoLink in Campbell.

Calhoun said condo prices moved down to $410,000 in January 2005 from $429,000 in December 2004. The median condo price was $355,000 a year ago January. January's condo sales this year, at 352, were off December's 472 and lower than last January's 375. The condo inventory in January, at about 440 was almost half what it was a year ago at 855.

Here's an area-by-area look at December 2004 and January 2005 prices and sales on single-family detached homes.

Campbell's median price dropped from $720,000 to $695,000. Sales dropped from 34 to 24. Los Gatos' price rose from $1.1 million to $1.38 million. Sales went from 30 to 24. Saratoga's price fell from $1.42 million to $1.41 million. Sales plummeted from 33 to 19. Santa Clara's price was up from $600,000 to $645,000. Sales were down from 70 to 43. San Jose's price rose from $625,000 to $635,000. Sales tumbled from 697 to 498.

Sunnyvale's price fell $109,000 from $750,000 to $641,000 due to more lower end sales, which fell from 60 to 37. Rose Garden's price likewise rose dramatically from $659,900 to $842,450 due to an unusual number of high-end sales. Sales fell by one from 17 to 16. Willow Glen saw a $700,000 to $749,000 price increase. Sales fell from 68 to 41. Almaden Valley's median slipped from $858,000 to $855,000, as sales dropped from 34 to 32.

Interest rates are moving along a more identifiable track. The New Year began with a national average fixed interest rate of 5.77 percent for 30-year conforming loans. That slipped four consecutive weeks to 5.63 percent nationwide, 5.61 percent in the West, according to Freddie Mac's Weekly Primary Mortgage Market Survey.

Calhoun said market-condition-based transaction decisions are almost always shunned, and right now is perhaps the most difficult time of the year to do so because seasonal data is inherently difficult to decipher.

"The stats are based on pre-holiday sales. It's less useful than at any other time of the year because there's such a dramatic change. It's not very useful in determining what the market is going to do going forward," Calhoun added.

Aldana says because of the seasonal nature of market current conditions and growing complaints against real estate agents, finding professional help is key, perhaps more than ever.

"There are more real estate agents than there are homes for sale because there are many new agents who lost other jobs. That means there are more agents with a lack of training," said Aldana, of LetsTalkRealEstate.com.

"If you want to get the upper hand you need to work with a agent who is knowledgeable in the market and has a good working relationship with the rest of the industry," he said.

Real estate writer Broderick Perkins, executive editor of San Jose-based DeadlineNews.Com, writes regularly for this newspaper.