Mexico, depending on where it is you are going. If you go to the more resort areas, you can probably spend a lot of money fast. Cuba, depending on where you are living, can be very expensive to visit.
(If you are American, it's still illegal to go there and you'd have to travel to South America or Mexico first, then fly over...and do the same coming back, but be careful!!).
Hawaii is possibly the most expensive place on your list to visit. It is an American state (which already makes it expensive to travel to). Airfare is expensive and everything on the islands has to be shipped in and imported. So, even a loaf of bread is around $5.
Mexico is probably your best bet.
And, depending on how you want to travel makes a huge difference. You can couch surf - look it up on the web under couch surfing and that's really cheap. Or, youth hostels are also very cheap. Hotels and resorts are the most posh and most expensive.