A little confused, in your first post it sounds like you're leaving for three months. (Not coming back to the same house, that much is clear.) In your last post you talk about maybe being out a long time. (And I completely get not knowing what life will be like a year out, I've come to the same conclusion my self
The stuff you keep for a three month cruise and the stuff you keep multi-year cruise are quite a bit different, to my way of thinking anyway. The main reason is storage costs money, in most cases, and the more you store the more it will cost you.
So if it were me, and I've given this a lot of thought, just a few years behind you, I would look at most of the items that you have from a cost of ownership perspective, with a sentiment parameter. If you've ever worked in manufacturing in the past 20 years, then you've probably heard of 5S or lean manufacturing or something similar. The idea is that every bit of space taken up by something costs money in some way. So you reduce inventory, excess tools, equipment (and people, in most cases... it is what it is). So just apply those principles to your stuff (except the people part, keep them around.) For instance, if a couch cost you $1000 new, 15 years ago, it might be worth $250 now, if it's still in great shape. If it will cost you ~$10/month in increased storage costs, because you needed to rent a larger storage cube, then that couch is break even at around 2 years. If there's a chance you'll be gone longer than two years, you'll loose money hanging on to that couch. So, unless it has sentimental value, I say get rid of it.
So in general, large items that you can replace when you get back, I would get rid of all of them. Appliances, kitchen sets, dining room sets, living room sets, bedroom sets (you'll want a new mattress when you get back anyway!) Get rid of all of it unless it absolutely can't be replaced. Great Aunt Hilga's vanity from the colonial days, maybe that's a keeper, or better yet, find a relative who would want it. But everything else, you can replace when you get back and it wont be costing you monthly.
Clothes, I would keep a set or two of formal/business wear if you aren't taking any think like that on the boat. It doesn't take up too much room and it's nice to have that kind of thing when you need it. Use a vacuum bag for storage of any clothes. Other than that, I would use the same rules as or the large items. If it's replaceable, get rid of it.
Decorations can be tough since they are often sentimental. But, if you have already off loaded the big stuff, you have more room for pictures of Great Aunt Hilga, etc.
Anyway, that's my general feeling about what to keep/toss. If you can get everything down to what will fit in a ~5x10 storage trailer you will go a long way to reducing you ongoing fixed costs, which will increase the amount of time you can cruise.
If you pass through Long Island Sound on your way south, send me a PM!