I was in the same place as you in my early twenties - In fact, I asked for advice, like you, and got similar responses.
I ended up purchasing a fat, slow, but "large" Bayfield 25 - I could stand under the companionway hatch, and the toilet wasn't under the "nookie board" of the v-berth - WOW!!! No world cruiser... That was my dream, but in the end I decided to do the ICW, and Bahamas - Abacos and Exumas. I'll tell ya, as another poster mentioned, there are years worth of cruising waiting for you in the Caribbean! If you like it, and want to keep going, either get some work down there (hard), or since the boat is so small, put her on blocks for a few months, go home and make some dough, then return!
The boat was less than perfect, I didn't have enough money, equipment, or security for my inevitable return. I don't regret it at all - was one of the best times of my life - spent a great year on-board island hopping.
Here are some things I would do if in your shoes:
-Get a part-time job at WM or another marine store - take the money and use it to outfit the vessel and only pay approx. cost +20% for gear.
-Get some tickets - STCW95, Navigation courses... You may end up being able to find some work as a skipper for a charter company down there.
-Live-aboard at the dock when most of the work is done - You'll save rent and learn whether or not you can live one the boat full-time.
-Go minimal on gear - get the safety and nav gear you need - but ask yourself each time "would I rather have an extra month(e.g.) in the islands or be able to have a digital readout of where the wind is coming from, etc..."
-Get good ground tackle - heavy anchors and all chain so that you are confident about anchoring and as such will not use marinas.
I'm sure there are dozens of things that I'm forgetting - email me and I'll be happy to help ya.
I hope you make it happen. It can be done - I was amazed by the number of guys in their 20's in small boats in the Bahamas - I always looked at it like taking a year off to go "backpacking" like many high school grads do before uni- except my backpack floated and was way nicer than a flea-ridden hostel!
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