There are many wonderful hotels on St. Barth, but I am not going to tell you about them. Whether you want to come here alone or with a large group, renting an apartment or house will almost always be less costly. As well, I personally believe it makes for a more relaxed trip since you have your own space. If you are concerned that you will have to clean and shop everyday of your vacation, put that thought out of your mind because most of these properties are professionally-managed and offer soup-to-nuts concierge services.
I have used the same leasing agent for years and she's never let me down. Ellie Bettle at Travel Keys is a bit of Villa Rental Goddess. It's safe to say the she's seen nearly every available property on St. Barth and she can advise you like no one else. Email Ellie with any questions about properties that you see on their website. There are a few that may not be on there, so reach out to her with even the most bizarre request and she will point you in the right direction.