The national median price for all types of previously owned homes was $184,300 - 11.8 percent higher than in March 2012.
In the eight-county Philadelphia region, sales rose 23 percent in March from February and were 5.2 percent higher than in March 2012, according to Prudential Fox & Roach's HomExpert Market Report.
Median prices rose $23,000 in March from February - to $205,000 from $182,000 - and were up 8 percent from $189,000 in March 2012.
John Duffy, owner of Duffy Real Estate on the Main Line, said inventory for sale appears to be lower this spring than last, even though data show an increase in transactions.
In Montgomery County, data compiled by Duffy's office show, there were 4,479 houses on the market in March 2012, while this March there were 3,800 homes for sale.
"There are many homes that have been on the market for an extended period of time due to either price, condition or both," Duffy said, so not all the houses for sale are attractive to even eager buyers.
Investor declines are noticeable in South Jersey communities.
In West Deptford, for example, there are 78 houses for sale, down 26 percent from 105 in April 2012, according to real estate website Movoto.com. In Mount Laurel, there are 315, down 29 percent from last year's 445.
Center City Realtor Mark Wade, of Prudential Fox & Roach, said reduced sales numbers are a reflection of inventory levels "and not due to the lack of ready, willing and able buyers."
"As we turn from a buyers' market to a sellers' market, the first step is inventory depletion," said Wade, "and that is true here in town as it is nationwide."
He said he sees buyers "becoming more motivated and more competitive with their offers, due to the lack of inventory," which likely contributed to the median price increase from February to March, "and I see this trend continuing for a number of years."
Contact Alan J. Heavens at 215-854-2472, firstname.lastname@example.org or @alheavens at Twitter.