Bali, it's one of those places everybody wants to go to, and not without reason. It has something to offer for everyone, from pristine beaches to happening nightlife, adventurous treks and serene highlands. I went to Bali for a week in May '09, a really short trip that left me craving for more. My advice is that although Bali is a really small island just week would not do any justice to the place.
Like most travel expenses a major chunk of our money was spent on air tickets, but Bali is very cheap, once you get there you could have a blast by spending less that 10$ a day. Kuta beach is a traveler's paradise with cheap accommodation, great food, exotic drinks and parties happening round the clock. Kuta is also a great place for water sports and offers some truly amazing dives. The trek up the still active volcano Batur is a must try for the adventurous traveler.
The only negative point about Bali would be a lack of public transport but chauffer driven taxis are one of the cheap luxuries there. For the authentic spa treatment avoid the crowded touristy places and head to Ubud, which a highland and also a place for some of them best gourmet restaurants usually run by cooking schools, which is why they won't put a huge dent in your wallet. One week all inclusive trip to Bali would cost $800.
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