4. Which money is used and which currency or cards should I bring to Iceland?
The currency used is the Icelandic 'krona', which exists only in the country. It is not an easy currency to find out of Iceland, so it will not be easy to exchange money abroad. It is a currency that can have daily nuances in the value of the exchange. On this website you can find a converter at the bottom of the page. See in the Converter the current exchange rate.
In almost all places in Iceland you can use the US Dollar or the Euro. You can exchange dollars, euros or any other currency at any Icelandic bank branch (namely at Keflavík International Airport).
Bank cards (debit and credit) can be used in all shops, accommodation and other services. They can also be used at ATMs which exist around the country.