Southern California ended 2012 with its strongest December home sales numbers in three years, San Diego-based DataQuick reported.

The December median sales price hit $323,000, compared to $270,000 one-year prior. 

The strong finish, which is attributed largely to robust investment activity, a record level of cash buyers and more sales gains due to move-up markets, pushed the median sales price up nearly 20% year-over-year.

“The housing market had more to offer in 2012 than many anticipated. A lot of markets not only found a price bottom as foreclosures waned but they started to see their first meaningful gains in nearly two years. Buyers on the fence were drawn back into the housing game by amazingly low mortgage rates, a brighter jobs outlook and, in some cases, a renewed sense of urgency,” said John Walsh, DataQuick president.

A classic case of supply-and-demand coupled with a shift away from distressed sales contributed to the solid December report.

In Los Angeles, Riverside, San Diego, Ventura, San Bernardino and Orange counties, a total of 20,274 new and resale homes and condos sold in December. This was a 5.1% jump from the 19,247 sales in November.

A large portion of overall sales in December can be classified as the move-up market, home sales between $300,000 and $800,000, increased 31.4% year-over-year.

“Last year should also be remembered as the year the move-up market awoke. If these upward trends hold, which requires a sustained economic recovery, we should eventually see more inventory hit the market,” added Walsh. “More would-be sellers will be satisfied with what their homes can fetch, and fewer people will owe more than their homes are worth, freeing them up to move. The rise in inventory would at least tame price appreciation.”

Click on the chart below to see the year-over-year change in the California metros included in DataQuick’s report.