Booking Ahead in Fiji

I am planning to visit Fiji for about 2 and a half weeks in November. One week will likely be spent at the Astolabe Reef Resort on Kadavu, and I know that I need to book way in advance there. I am wondering if I need to book tours and places to stay ahead of time in November, or can I just show up and find a place to stay. I would be looking to stay in a room rather than a dorm. I will be staying in Nadi, Suva, Pacific Harbor and maybe Taveuni.

Nadi, Suva and Pacific Harbour have lots of accommodation options. Booking ahead might only be necessary on Taveuni if you want something with an ocean view or have budget concerns as the better-
value places can get booked.