?..Also, for those LA's in the northeast, how do you manage the winters?
Is living onboard in the winter a real challenge?.
I've not done it, but know many who have. My slip neighbor did so last season for the first time.
Elements: you want to keep the snow and ice off your decks, so shrink wrapping or a custom cover are necessary, IMO. They definitely have a greenhouse affect and you'll be in shorts and t shirts in the cockpit on sunny days.
Heating: lots of options. None are really a good idea to leave on while you're away. So what keep things from freezing while you're not aboard? Some take their chances, some burn.
Sewage: some marinas provide no accommodation, so you'll always go ashore. A real PITA. Other bring a pump to you on a fixed schedule. This often requires that you route a hose from you pump out fitting to a place they can access,,whether you are there or not. My neighbor described how his slipped off once. Your imagination will suffice.
Fresh water: your probably going to hump it in jugs from shoreside, otherwise, go, without. The good news is, your storage tanks probably won't freeze, depending on water temps. At least they have enough mass to take a while and you'll likely be back with the heat in by then. It's your fresh water lines that may run near your hull that are in danger.
Finally, the biggie....... CONDENSATION: your boat will naturally be closed up with little air exchange. Everything from you exhaling, cooking, any flame, all produce enormous water vapor. That finds places to hide and mildew can be rampant.
If I were to live aboard in winter, I would absolutely, positively, mandatorily have a dehumidifier running 24/7. Hey, you could capture the condensate and use it to clean dishes.