The median price of a Marin County, Calif., home spiked 15.5% to $952,250 in November, compared with the $824,500 median price a year earlier.
Irvine, Calif.-based CoreLogic said sales of new and resale homes and condos also rose 18.1% to 320 homes sold in November, up from the 271 homes sold in November 2016.
Across the Bay Area, the number of homes sold dropped in some counties, but prices rose everywhere, said CoreLogic research analyst Andrew LePage.
"The Bay Area's record median sale price in November and the relatively large annual median price gains logged by some of the region's costliest counties reflect more than just home price appreciation," LePage said. "At the regional level and in some counties, the median sale price got a boost from a 'change in market mix,' where a higher share of sales occurred in mid- to high-end areas.
"Tight inventory and affordability constraints have suppressed sales in lower-cost areas," he added. "The result is an upward push to the median sale price — the point at which half the homes sold for more and half for less."
Marin real estate professionals said the lower end of the Marin market — $1.7 million or less — is seeing high activity due to low inventory, while the very top end over $5 million is quiet.
"It's definitely slower in the upper end," said Barbara Major of Golden Gate Sotheby's International Realty in Mill Valley. "But under $3 million is great, great, great."
At the lower end, "the inventory isn't even there — I have 10 to 12 clients and we can't find anything," Major said. "For $5 million and up, they're just sitting."
Tom Dreyer, also of Golden Gate Sotheby's International Realty in Mill Valley, said he sees "persistent demand for anything that is liveable or well-located and has upside potential" under $1.7 million in Central or Southern Marin.
"We're living in the Marin bubble, which is the ethos that we are fortunate to be living in this environment and those who can afford to live here are extremely fortunate in relation to 90 percent of the country," Dreyer said.
He sees a "very good economy" for sellers, but a "challenging" one for buyers in that only those who have "strong financials such as excellent jobs, excellent credit, significant down payments or all-case buyers" are able to win the competition for a Marin home.
The all-cash buyers phenomenon started about 2011, Dreyer said, when prices were going down and speculators came in to pick off lower-priced properties.
Jennifer Harris-Marks, of Coldwell Banker Residential, said the bump in Marin home prices is due to a "severe lack of inventory, combined with several continuous months of buyer demand that has not been met."
She said demand has been so great that "close to 50% of the homes I sold this year were sold off-market for over the asking price."
Buyers may also be concerned about the possibility of mortgage interest rates rising, so "people want to get into the market now and secure the lowest mortgage rate possible," she said.
At present, Dreyer said, there are only 15 homes available in Marin for under $1 million.
"There are 56 on the market (for under $1 million), and 74% of them are under contract (in escrow)," he said.
In the $1 million to $2 million range, there are 104 on the market, with 52% under contract, Dreyer added.
From $2 million to $4 million, 52 homes are on the Marin market, with 30.7% under contract.
From $4 million to $6 million, 18 homes are on the market, and 27.7% are under contract.
Over $6 million, 10 are on the market but none are under contract, Dreyer said.
He sees the Marin housing market continuing strong in 2018.
"As long as the stock market continues to be as high as it is and unless there is a change in the local tech economy or financial services, I would expect consumer confidence to remain high and we'll have a good spring market," he said. "We still don't have enough inventory for all the people with good jobs (who want to live here)."
According to LePage, the median price paid for all homes sold in the San Francisco Bay Area reached a new peak in November at $787,000.
"This was up up 12.6% year over year from $699,000 in November 2016," he said. "The San Francisco Bay Area's previous peak median sale price was $775,000 in June and October of this year."
LePage said sales were down in November across the Bay Area.
"In November, sales of newly built homes — detached houses and condos combined — were 25.9% below the long-term November average, while resales were 1.5 percent below the month's average," he said.
