April Home Sales on Slow Upswing : Real estate: The housing market continues to improve. But the numbers are still down 20% from last year.

The area’s housing market continued its slow improvement in April, as sales of existing single-family houses and condominiums in the Valley rose 7% from the previous month, the San Fernando Valley Board of Realtors said Monday.

But the 939 sales reported in April were down 20% compared with a year earlier, and real estate executives expressed concerns that the recent riot in Los Angeles could affect sales in May.

By comparison, in March, home sales increased 12% from February and surged 59% from a year earlier.

Lorrie Griffey, president of the Valley realty board, said real estate agents saw little activity on the first weekend in May after the riots. And that could very well show up in the numbers at the end of the month, she said. Open houses are usually held on weekends, and offers are often made then as well.

Griffey said there were signs that low interest rates and a large inventory of houses were continuing to bring out buyers. “There seems to be a pent-up demand,” she said. Advertising is drawing more callers than last year, she said, and it appears that sales “will hold steady.”

However, the inventory of unsold houses and condominiums in the Valley rose 6% last month to 13,653 properties, and remains near its record high.

In April there were 692 sales of existing single-family houses in April, up 3% from the previous month. The average resale price for a single-family house was $297,600, up 10% from March, and up 4% from April, 1991. The median price for single-family houses was $227,000 last month. (The median price means half the homes sold for more than $227,000, and half sold for less.)

Resales of condominiums totaled 247 last month, up 18% from March. The average sale price for a condominium in April was $154,800, down 3% from March, and marked a 4% increase over a year ago. In April the median condominium sales price was $145,200.

The Valley realty board, the largest in California, reports housing sales by its members in the area from Agoura to North Hollywood. Its statistics do not include sales of most new residences.

April Valley House Sales North West: Avg. Price: $327, 400 Sales: 29 North Central: Avg. Price: 270.700 Sales: 94 North East: Avg. Price: $177,800 Sales: 99 South West: Avg. Price: $324,900 Sales: 219 South Central: Avg. Price: $333,700 Sales: 103 South East: Avg. Price: $324,000 Sales: 148