Hundreds of condominium residents are preparing for darkness due to a management dispute with Con Edison.

Con Ed says the building at 1 Landmark Place owes $100,000, and if the money is not paid, the building will lose its electricity Monday.

Residents say they paid Kravetz Realty Group, the building's management company, hundreds of dollars a month for electricity. Now Con Edison wants its money, and no one in the building knows where their payments to Kravetz actually went.

Kravetz could not be reached for comment, but Con Edison says the issue is still not resolved, urging the management company to reach a payment agreement by April 13.