Money, phones and wifi in the Cook Islands
A few practical things that are easier to know in advance.
Money
The New Zealand dollar is the currency. The Cook Islands also mints its own coins and a distinctive three-dollar note, which make good souvenirs but are not accepted outside the country. Cards are widely taken in hotels, restaurants and larger shops; markets and small operators often are not.
Phones
Local SIM cards are available and are usually cheaper than roaming. Coverage is good around the coast road and thin in the interior.
Internet
Considerably improved since undersea cable, but expect it to be slower and more expensive than at home. Wifi at accommodation varies enormously — if you need to work, ask specifically before booking rather than assuming.
Book something on Rarotonga
Booked direct with local operators — no booking fees.