I wouldn't buy a 380 for this purpose
I'm sure the boat is plenty tough. And I am sure someone uses it for long passages. But the boat was not designed with this in mind. Because of that, there are a lot of small things that just aren't suited to this purpose. Many can be fixed, but at the end of the list, you might have been better to start with a different boat. Here's a few.The 380 has no sea berths, that I can tell. On a circumnavigation, you'll spend weeks at sea. Sleep is important. A sea berth is aligned along the boat's axis. The 380's aft berth is athwartship, and its left settee also is too askew to be comfortable, unless you like sleeping with your head above your feet, and vice versa. You might be able to fashion a seaberth out of the U settee. But you really want two or three. (As a couple, you'll often look for third and fourth crew to help on longer passages. And on some tacks and angles of sail, a specific berth becomes uncomfortable.)Surprisingly, for a 38 foot boat, it has a small nav station. You'll be adding SSB, weatherfax, likely a laptop. The larger the nav station, the better.The 380 is a beamy boat with moderate ballast, which means that it will have a quick motion and get knocked about a lot. There's nothing you can do about that. It also has a spacious saloon. You'll need to add interior grabrails. The 380 looks to have only moderate storage, of the sort that is secure underway. It has little outside storage. You'll be surprised how much you want to bring along for a short voyage. Much more for a circumnavigation. Boats designed for voyaging sacrifice interior space to lazarettes, lockers, bins, and even more lazarettes. Most likely, you'll end up using the V berth or aft stateroom for storage. But you'll need to fashion a way to hold things in place. Hunter is famous for providing a lot of dealer support. Unfortunately, that doesn't help you in Aden. Or even in Tortola. Cruising is largely the art of fixing your boat in foreign ports. From its large custom ports, to Hunter's prediliction for creating inaccessible parts of the boat, this is not a boat I would want to mainain for a three year trip. (Speaking of ports, every voyaging boat should carry plywood or other covers that can be nailed over a port that breaks. I'm not sure how you would manage that the 380's large side ports. And make sure to put those covers on your list of things that need to be stowed.)There's more. But all that said, I'm sure you can do this. Most problems have solutions of various sorts, and you can just put up with the ones that don't. The only question is, Why?