VALHALLA, NY-Cognet Corp., a software management technology firm, has expanded its presence at the Sutton Park office complex here with a new lease for 16,827 sf of space.

HARTSDALE, NY-Retailer Marty's Shoes has signed leases for three new store locations in Cortlandt, Mamaroneck and Yorktown, bringing its number of Westchester County outlets to a total of nine.

SCARSDALE-Gas service station operator BP-Amoco is looking to open a total of 15 new locations in the Hudson Valley over the next year.

WHITE PLAINS-An affiliate of Starwood Hotels & Resorts Worldwide Inc. has acquired the remaining 50% interest in the Sheraton Centre Toronto for approximately $48 million.

STAMFORD-The Wiggin & Dana law firm will more than double its office presence here when it relocates its operations in the next few months from 3 Stamford Plaza to 37,000 sf of space at 400 Atlantic Street.

WHITE PLAINS-The prospect of brown outs, rolling black outs and significant energy cost increases in New York State will be the focus of a Building Owners and Managers Association of Westchester meeting on April 12.

WILTON, CT-Fairfield Chemical Carriers Inc. has relocated from offices in Darien to 3,434 sf of space at 5 River Rd. here. Wilton Shopping Center Limited Partnership owns Fairfield's new space.

DANBURY, CT-In just a few weeks of active marketing, 50% of the available units in Phase Two of the Kensington Woods townhouse community here have been sold.