Money & Shopping
The local currency is the Maldivian rufiyaa (MVR), divided into 100 laari. However by law, resorts price services in US dollars and require payment in hard currency (or credit card), so there's absolutely no need to change money if you're going to spend all your time at the resorts. Most hotels have a shop but this is limited to diving and holiday essentials (sun cream, sarongs, disposable cameras, etc.) Some excursions from resorts will take you to local islands where there are handicraft type things to buy, but they are typically made outside the Maldives and sold at outrageous markups.
If you are heading to Male or the other inhabited atolls, exchanging some rufiyaa will come in handy. The coins, in particular, are quite attractive and make an interesting souvenir in themselves, but the smaller denominations are rarely used or seen. The official exchange rate to the US dollar is floated but practically 15:1, but while dollars are near-universally accepted, shops usually exchange them at 15:1 or even 10:1.
Tipping is not compulsory in the Maldives as 10% service charge is added to everything - but given the low salaries earned by the staff and the excellent level of service generally offered, it is a nice gesture to help the staff of resorts to earn some extra money. It is also not entirely certain that the 10% service charge is passed on to the staff.
Over the years the tipping culture has changed in the Maldives, mainly due to Europeans and visitors from other continents giving varying amounts of cash as tips.
Maldives are expensive for those who have comfort- and service-oriented tourism in mind. Resorts have a monopoly on services for their guests and charge accordingly: for mid-range resorts, $1000 per week per couple is a conservative budget for meals, drinks and excursions, in addition to the cost of flights and accommodation. Practically anything — including hotel rooms if booked locally — gets slapped with an arbitrary 10% "service charge", but tips are expected on top.
For an adventurous traveller who has time, Maldives can be a very affordable and rewarding experience, with prices comparable to Malaysia. A number of inhabited islands have guesthouses with typical prices 25-40 euros per room. On more remote islands, renting rooms in villages is possible at even less than that. Food is inexpensive (and fish curries are delicious). Public ferries will transfer you between different islands of the same atoll for a few US dollars (though for less obvious locations, there will typically be 1 ferry per day and no ferries on Fridays). For transfers to remote atolls, one can negotiate with cargo boats, which would often take people for 15-40 US dollars, depending on the destination. Cargo boats do not have schedules and depart when loaded. One may expect 1 boat in 1-3 days for each atoll.
It is important to have in mind that staying on inhabited islands implies respecting the strict Muslim norms including no alcohol, modest dress, reserved behaviour. However, the locals are very welcoming and the experience may be much deeper and more rewarding than staying in resorts.