First it was the Château Royal Hotel, then became (after a much needed renovation) the Château Crescent Apartments, located at 1420 Crescent, right in front of Winston Churchill’s . The word out (via tipster) is that they are planning to do a condo conversion. We haven’t yet checked if the rumors are actually true, since no tenants seem to have a clue about it.
Right now the building is advertised for rent and according to the Montreal Gazette ad, the rental prices are between $785 to $1245/month- we’re not sure what’s included.
They have also a few rental ads on CraigsList:
Posted by: Deya Bautista - Real Estate Broker working as part of the McGill Immobilier team. Specializing in high end condos in downtown and Old Montreal. For buying or selling contact Deya at: 514.917.7889 
if this ever comes up for sale let me know…