"We have to pay above 5k for a 2 Br in the UES through the end of April, when our lease expires. Is there any tactic that can work negotiating with our managing company before our lease is renewed?"
"Play hardball. Get the list of grievances that someone had commented about, and add to that the following: tell him that you are working with a broker and he/she has found you an apartment that is several hundred dollars (pick a number) cheaper than yours, AND they are offering one month free to help with the moving costs. If he asks "where", tell him you do not wish to disclose the exact location, but you will fax him the offer with the address concealed." ["Renter’s Market in Manhattan? You Betcha!"]