In the NYC area "most marinas" and "winter" are alien concepts. Most shut down for the winter, and the rest are terrified that someone will fall off icy docks, they claim insurance will not let them operate in the winter because of this. Out of what's left? Well, a number pull moorings. Some actually don't have the shoreside bathrooms operating in the winter, there's only the "employee" one in the shop or office, don't expect a shower.
Anyone who thinks this is sunny Florida where they can expect to find liveaboard space--on a dock or mooring, clandestine or tacit--and do it year round, is in for a real surprise. A lot of shoeleather can be spent looking and asking, and it will have to be shoeleather because no one will give a quiet wink over the telephone.
This is *not* an easy place to find liveaboard space. Ignoring the NJ marinas on the Hudson (last I'd heard PI wasn't the only one that allowed liveaboards) AFAIK
, the only place that legally and openly condoned liveaboards was the West 79th Street Boat Basin, and the only way to get one of those slots is to buy the buy that is in it. That's also changing, as the city tries to get rid of derelicts in the mud and rebuild the marina. Haven't heard how the latest round of lawsuits there has gone.
Haven't heard anyone, in at least a decade, actually cite one other place (by name) that actually accepts liveaboards in NYC proper. Even up on City Island, where space has been tight for a long time (too many yuppie condos) and the "short ride" to downtown Manhattan is about an hour long, bus to the subway at the end of the line, and not considered a particularly safe line to ride during off hours.