Brooklyn, N.Y.—By July, potential home buyers considering a condo at the BellTel Lofts here will have an extra incentive to sign a contract—the development has won a tax exemption from the city that will cut projected monthly property taxes for homeowners roughly in half for 10 years.

“The response from residents and prospective buyers has been exceptional,” says J.J. Bistricer, executive vice president at developer Clipper Equity. Property tax breaks have recently become much harder to get in New York City since officials revamped the system of exemption offered to new residential developments.

Condominiums like BellTel can use all the help they can get as the local real estate market slows. The first apartments at BellTel went on sale in October 2006. Now both phases of the 27-story high-rise have finished construction. More than half of the 250 condos at BellTel have closed sales at an average price of $744,000, according to www.StreetEasy.com.

Built in 1929, BellTel Lofts was originally designed by architect Ralph Walker and designated a landmark by The New York City Landmarks Preservation Commission after serving as the headquarters for the New York Telephone Co.