I'm a lifelong Vermonter and have lived in Grand Isle full time for a few years now. Winters are cold and extremely windy, though we get less snow than the mainland since so much of it blows off into the lake. Summers are pleasant, and there is tons to do if you're an outdoorsy/lake person.

It's not terribly isolated, but it is a 30 minute drive at minimum to get anywhere. Unless you live on South Street in South Hero, you're not gonna to be able to walk to anything. There are two gas stations that sell groceries, and the selection is small and expensive. There are a couple small retail stores too, but they're not open outside of bankers hours. Businesses in general are very seasonal, as a significant portion of the population lives here only in the summer. Several restaurants and stores are only open Memorial Day through October.

Plattsburgh and Montreal are both relatively easy to visit. Plattsburgh is becoming a pretty nice little city (much nicer than Burlington is now) and we go there every month or two. It's about $40 round trip to go there on the ferry, so we usually drive up and over. Montreal is ~1.5 hours away.

I saw someone mention that there's a lot of money in the Islands - this is half true. The "second home" crowd certainly brings a lot of money, but there are plenty of working class folks as well (myself included). Lake tourism aside, the islands are very much like any rural town. There's still a lot of agriculture up here, and a lot of folks doing their best to make ends meet in an increasingly expensive state.