May homes sales in Sonoma County remained at their highest level for the month in eight years.

Buyers purchased 505 single-family homes last month, according to The Press Democrat’s monthly housing report compiled by Pacific Union International Vice President Rick Laws. That was one more home than sold in May 2012 and the most for the month since 558 homes were sold in 2005.

The median price last month declined 2.4 percent from April to $425,000. Despite the dip, the median remained 29 percent higher than a year earlier when it was $329,500.

The inventory of available homes fell to its lowest level for the month in 13 years. May ended with 755 homes for sale, the smallest number since 657 homes were on the market in the same month of 2000.

“There’s a slew of buyers, and there’s nothing for them out there,” said Mike Kelly, an agent with Keller Williams in Santa Rosa.

Even so, Kelly expected inventory would start to slowly increase. And he noted that some sellers are finding they have overpriced the homes and are meeting resistance from buyers.

For the Bay Area, the median price for all single-family homes and condominiums rose 1.8 percent from April to $519,000, according to DataQuick, a San Diego-based real estate information service. The median increased 29.8 from a year earlier and was the highest for the month since March 2008, when it was $536,000.

Sales declined 4 percent from a year earlier to 8,541 homes and condos.

Distressed property sales, including foreclosure resales and short sales, made up 21 percent of all transactions in the Bay Area last month, DataQuick reported. That was the lowest level for any month since December 2007, when such sales made up about 21 percent of the total.

Check back later for the full report.

— Robert Digitale