Sorry to hear about your back troubles. It's so debilitating.
My wife had bad sciatica two years ago when we went to the SVI and she could hardly do anything. Fortunately we had a family of 5 with us that could help run the boat. I'm hoping to go back there now that she's doing better. She missed out much of it, and it's a beautiful place.
If we couldn't sail I'd definitely think about a trawler or power-cat.
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