The St. Lucia base is very nice and in a populated area. There are a lot of options for beer, wine, groceries, restaurants, etc.
The last time we visited, the walk from the marina buildings, bathrooms, restaurants, customs, etc. was quite far. You can get an idea from the picture attached to this post.
VERY IMPORTANT: You'll be lucky if you find a working ATM and they have a maximum withdrawal amount per day of $200 USD (if memory serves). There are a lot of places to use cash in the Windwards so ensure you have enough to cover mooring balls, boat boy purchases, etc. One lobster meal brought to your boat can put a large dent in your cash.