VALHALLA, NY-A New York City-based law firm has significantly expanded its Westchester operations and has relocated to 14,000 sf of space at 200 Summit Lake Drive here, according to Howard Properties Ltd., which brokered the deal.

NORWALK, CT-The renovations aimed at attracting high tech companies to the Norden Systems complex here are nearly complete and the ownership is now marketing the available space for research and development, data center or disaster recovery uses.

PURCHASE, NY-RBC Capital Markets, which will be reoccupying its space at One Liberty Plaza in New York City soon, will be shifting some its personnel to a new 40,500-sf office here at 287 Bowman Ave.

NEW ROCHELLE-A host of city dignitaries, including Mayor Timothy Idoni were on hand for the grand opening of Summit at New Roc, a $22-million rental housing development built on top the New Roc City parking garage here.

HARRISON-W&M Properties reports it has secured two lease deals at the 500 Mamaroneck Ave. office property here, including the relocation of accounting firm O'Connor Davies Munns & Dobbins, LLP to more than 11,000 sf of space.

TARRYTOWN-In the largest lease transaction in Westchester County since the terrorist attacks of Sept. 11th, Quaker Foods & Beverages has signed a long-term lease for 23,495 sf at 660 White Plains Road here.

ELMSFORD, NY-Mack-Cali Realty Corp., reports it secured more than 240,000 sf in lease deals in its Westchester/Connecticut portfolio during the third quarter of this year.

TARRYTOWN, NY-In the largest real estate sale in Westchester County so far this year, Equity Residential Properties Trust has acquired the Talleyrand Crescent rental townhouse community here from an affiliate of Cappelli Enterprises of Valhalla for $61 million.