The percentage of customers signing offers in January increased by 12 percentage points according to a leading brokerage and 23 percent of Americans think it is a good time to sell compared to 11 percent the same time last year, according to Fannie Mae’s January 2013 National Housing Survey results.

Customers signing offers increased 70.4 percent in January, compared with an increase of 58.5 percent a year earlier and customers requesting home tours were up 57.9 percent in January, compared with to 52.0 percent in 2012 according to Redfin’s Real-Time Demand Pulse.

The increase in homebuyer demand seen in January paired with a nation-wide inventory shortage has created an extreme seller’s market, the brokerage said. Particularly in Redfin’s Southern California markets, bidding wars involving thirty or more offers have become increasingly common.

Fannie’s Mae’s monthly survey found that while expectations regarding personal finances stayed relatively flat, other housing indicators remained at or near survey highs, indicating consumers remain confident in the stability of the housing market.