Seattlesailor is right, but I was wondering why you'd need such a large crew. I recently saw a 180 foot, three masted schooner that had a crew of 9, and 4 of those where Stewardesses/cooks. It had hydraulic roller furling on just about everything , and hydraulic self-tailing winches. and everything was operated from the helm. Most 40+ foot boats will do just fine for your uses. They sleep 8 to 10 and can be sailed with as few as 3 crew. They are much less costly to own, and maintain. I hope this helps.
First learn to sail! Don't even think boat till you have done this. 1st rule of sailing. The only day you will be happy"er. Than the day you buy your first boat. Is the day you sale it.
To accommodate a crew of 15 or 16 you will need a fairly large sailboat, it can easily be in the 75' to 100'+ range and cost a million or millions of dollars. here is an example of one. there are many others available depending on your budget.
hope this helps
The information you seek can be found at the link below. It covers off-shore and also links to another excellant site on in-shore. You'll find help with everything from learning to sail, to choosing the right boat... provisioning and equiping your boat, and what you can expect "out there" when sailing from one paradise to another, and even on around the world... It is an excellant site - can't be beat!
Happy and Safe Boating!