All too often when people go on vacation they stay at resorts, and in many cases never leave. Sure, it's a vacation, but you are in another country (or in this case, a US territory), so you don't really get the whole experience.
The Green Iguana is right in the thick of things. Assuming you have rented a car, you can get to Magen's Bay, Bluebeard's (nice restaurants), the grocery store, and of course downtown Charlotte Amalie in a matter of minutes. This in not a hermitically sealed location.
The managers, John and Gwen, are fantastic people. At a normal resort, if you want a beer, you go to the bar, pay $5 for it, and maybe talk to the bartender because it's his/her job to talk to you. At the Green Iguana, you go to the office, drop $2 on the counter, get your beer, then (in my case), plop in a chair and and talk to John and Gwen about tattoos, healthcare systems, what that weird bird is, which beach to go to, where to find the best sushi (Enkai), and the effects of too much green beer over St Patrick's day. Pretty much anything. They are great.
The rooms are light and airy. We were in H2, which had a microwave, safe and coffeemaker; it's also cleaned and the beds are made every day, unlike some places I've stayed, and nicely appointed. We had a huge balcony overlooking the tow and bay. We spent a lot of our time just chilling on the balcony. The room was clean and had everything we needed.
There are two building separated by a loverly courtyard. There are hummingbirds, iguanas (of course), lizards, all sort of fauna. We spent a lot of time chatting with Joh and Gwen, and other guests. The property is one of the few that doesn't have a 3-night minimum, so a lot of people are there for a night prior to going on sailing charters. We met a lot of really cool people; the general vibe was very low-key.
A lot of people leave things, which go into a sort of "lending library": fins, snorkels, beach chairs, all sorts off stuff, all of which is available to whomever want to use it. Renting a chair at the beach for $10 a day can add up quickly, so we saved a few bucks. Although there isn't a proper gift shop such as you would have at a resort, they maintain a lot of small items such as toothbrushes, OTC medicine, soda, beer, water, cereal, etc. Very handy.
John and Gwen have a wealth of information regarding places to eat, where to rent a car, excursions, etc. St. Thomas is a quirky place in terms of when things are open, when they close, where to get the world's best roti, this really cool cheddar/blue cheese, where to get a sandwich, the best grocery store, etc. You might get that information from the desk clerk at the Marriott, but probably not. They were also invaluable in providing direction. The roads are poorly marked in terms of signage, so directions are generally based on landmarks, and you can't get that from Google.
I was in contact with Gwen for several months before we came. I'd asked about where to rent a car, and the local place she suggested was significantly more expensive than the majors (Budget, Avis, etc), but I trusted Gwen's recommendation, and it was worth every penny. A quick plug for Amalie Car rentals; I got a 2013 Jeep Wrangler with 2500 miles on it. If you plan on renting a vehicle, get a jeep from Amalie Rentals. The hills and switchbacks are horrific, and a small jeep is the perfect vehicle for getting around, and you can take their vehicles off-island on the car ferry to St. John.
I can't emphasize what great people John and Gwen are. They always had time for our inane questions, great recommendations for, well, anything, and really put the icing on our trip. I can honestly say my wife and I both feel we made some new friends. How often can you say that about the manager of a hotel?
If you are traveling with small children, the Iguana may not be the best choice, as larger properties are more apt to have other kids, and kid-centric amenities. But if you have older kids, or you left them at home like we did (bravo for not burning the house down!), it's a great place to stay. I go on vacation to relax, not to drink my face off in a bar or go to a disco. So if your idea of a vacation is nice people, a lot of quiet, and an inexpensive rate, the Green Iguana is the ideal choice.