If you have a tight time schedule and the travelling distance is not too far, you may be better off taking a taxi. Taxi networks are on Viti Levu, Vanua Levu, Taveuni and Ovalau.
They are often plentiful in the main areas such as Nadi and Suva. They are very inexpensive as there is a lot of competition but it is always wise to ask how much the fare is going to be before you agree to travel, in the main areas it is metered but in some areas they are fixed, so always ask.
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They are easy to hail down
Taxis are easily organised at most
resorts / hotels
Taxi’s are plentiful at Nadi Airport