Sears, Roebuck's profit rose 24.7% to $409 million in the third quarter. While Sears merchandise group's income was flat for the quarter, Allstate's income was up 19.7% to $240.5 million. Allstate benefited from a $33.3-million "fresh start" adjustment under the Tax Reform Act of 1986. In addition, Coldwell Banker Real Estate's income jumped 512.8% to $47.8 million. The increase resulted primarily from the sale of a shopping center. Dean Witter Financial Services posted a loss of $4.2 million for the quarter. The Chicago company said revenue rose 9.1% to $12.19 billion.