<blockquote>Would it be impractical/unsafe after much reading and the above classes to jump on a boat and take off for a few years?</blockquote>
Quite right: absolutely impractical and unsafe.
It''s certainly possible to buy a used boat for the price you mention, and throw in up to half as much again to fit it out properly for your purpose. No problem there.
And you''re intelligent, enthusiastic, flexible, and still young and hale. Those are all points in your favor.
However, even given the classes mentioned, and allowing for a voracious reading regimen, you will need to add enough time to your equation to allow you to gain the experience to embark on such a foray successfully, i.e., time enough to become a sailor.
Let''s assume that you complete your classes in one summer; that you purchase a boat during that first off-season; that you then spend your weekends working on it; and that you spend evenings immersing yourself in a pertinent course of study. And let''s assume you are extremely fortunate in your boat purchase, and only require two years of weekends to repair/refit your craft. (Can''t devote every dollar of your disposable income, or every hour of your weekends? I''m not a slave-driver: take four years). <b>Where will you fit in the actual sailing time that will let you gain the on-the-water experience that will allow you to lose sight of land?</b>
I''d suggest, very humbly, that a much more efficient, and emminently more practical and safe, path to your goal would be to take the classes, then as you do the reading, purchase a trailerable weekender, around twenty feet or so, that you can use to daysail and then extend your range into weekend mini-cruises. That way, you''ll be able to take all the meat of those classes and reading, and season it with salt, as it were.
After at least one season running empty halyard shackles up to the masthead and untangling the mainsheet from around your feet, begin to take a look at yachts in your local market to see what is available that will meet your requirements. This exposure will bring up all sorts of questions and reveal huge gaps in your knowlede that will steer your education from basic sailing skills to the question of what boats of what types in what age ranges and conditions of what capabilities will be suitable for your plans. It will take at least one off-season of educating yourself, sorting through these options and narrowing your choices before you can think of entering the market looking to buy. Try to shorten this time/learning step, and you may be saddled with an expensive, long-term project/money pit/nightmare/albatros hung ''round your neck, out from under which you may feel you will never wriggle. You will have solved one problem: but it will be the seller''s problem you''ve solved. <em>Caveat emptor</em>.
If you''re really sharp, and have put in 400 hours, as a bare minimum, of coastal cruising in the weekender (even giving you credit for a full 48-hr. weekend, that''s only eight weekends: better to spend two seasons) you may be ready, <em>if</em> in that 400 hours you have gotten real <u>hands-on experience</u> working with charts, and in navigation, piloting, heavy weather tactics, anchoring/mooring, and meteorology.
That will take three sailing seasons or so, or whatever the minimum time will be required to educate yourself for/purchase/repair/refit a suitable boat, and will require sacrifices in your finances and social life to accomplish.
Now that the boat is nearly finished and you know how to tie a knot and shape a course, it''s time to scrape together a cruising kitty. You want to be gone two to three years, so the question is: how much money will it take to live on and keep the boat in reasonable repair for two or three years? This figure varies for every boat and cruiser, generally growing along with one''s age and waistline, and the attendant amenities such as refrigeration or the need for a night life ashore.
For sake of argument, I''ll use a gross income of $40,000/yr. Can you save 30% of your <em>gross</em> by living frugally? Then you will have $12,000, plus a few bucks in interest. Will that last you two years? Tropical cruisers report monthly budgets ranging from a spartan $600/mo to a few who spend in excess of $1200/mo. Split the difference and estimate $900/mo. That''s thirteen months of Carribean cruising. You indicate a desire for a cruise from two to three times that duration. Given these numbers, that''s three years of saving, once the boat is repaired/refit/provisioned. You can shorten the total time if you sell off assets, like the weekender. You''ll have to work this out using specific figures of your own.
You asked for responses concerning the practicality and safety of buying a boat and setting off with minimal education and no experience. You certainly can jump into it without solid experience underneath you. Just make sure you bring a working flare gun.
These are just my thoughts. Hope this gives much food for thought, and encourages other posters to give contrasting viewpoints.