(By Kirsten Valle Pittman, kpittman@charlotteobserver.com) Charlotte-area home sales improved in March, indicating consumers are feeling more confident about the economic recovery, local real estate experts said today. But prices remain weak, a sign of continued challenges in the market.About 1,900 houses, townhouses and condos sold in the Charlotte region last month, up 43 percent from February, according to new data from the Charlotte Regional Realtor Association.