There are some choices in Connecticut.
I store at Captains Cove in Bridgeport - cost is $55/foot. The yard IS DIY and you can do bottom paint, sand, et al. I often see boats from New York, even New Jersey, store their boats here. The people at Capt' Cove are wonderful and I've not had an issue working/storing there in 6 years as long as you follow the rules.
Milford Boat Works is reasonable at $50/foot - and you can do your own work there too.
Another poster mentioned a yard up the CT River - a friend at the Yacht club mentioned the same marina - but there name escapes me - I believe the cost was somethign like $28/foot.
Since you must be in NYC - City Island may be your best bet.
In thinking of location - remember that you;ll need to be driving to the yard several times in the spring to commission her. So you need to consider driving time, etc into that equation - so good project planning is critical if you are driving a long distance..
At the end of the day - buying a boat is not expensive - winter storage is!
After a too-short first season as a brand new boat owner, myself and my partner are looking for somewhere to store our 25' O'day, the Gypsy Lass this winter. The boat is currently moored at City Island, but we wouldn't mind spending the winter in the city, on Long Island or in Connecticut. We're open to wet or dry storage, and our key concern is price. We're the sort of people who prefer to do our own bottom painting and maintenance, but if there happens to be a yard or marina with a good package deal then we'd be happy to go with that.
So does anyone know of an affordable yard, marina, or barring that a decent hauler and storage space around Long Island/Conn/ or New York? My co-owner and I are both students with somewhat limited funds, and could really use some advice about where to keep our Gypsy Lass!