Currency - Nepal the currency is the Nepalese Rupee (NPR). This is fixed to the Indian Rupee and is a soft currency, which means it cannot be changed outside the country. It is fixed to the Indian Rupee at 100 IPR to 160 NPR.
It is best to bring a mixture of cash and travelers’ checks in major currencies - USD, CAD, EUR, AUD - and ensure you have a mixture of large and small denominations.
Exchange - Money may easily be exchanged at Kathmandu airport on arrival and banks and licensed moneychangers in the cities (shop around as at money changers, a small amount of bargaining can sometimes get a more favorable rate). Bank rates and commission tend to vary. There are many licensed moneychangers in Thamel and Pokhara, though anywhere else is more difficult. The rates at the money changers is slightly lower than banks, but their opening hours are longer and usually you don’t have to queue. There are a number of banks that can provide money transfers and foreign exchange. Standard Chartered is the only international bank in Nepal and has several branches in Kathmandu and Pokhara. Outside of Kathmandu and Pokhara however, banks are unlikely to be able to provide these services.
Credit cards and ATMs - Credit card cash advances and ATM withdrawals are in NPR only. ATM machines can be found in Kathmandu and Pokhara, and other larger towns, but not in smaller places. Outside these places, in general credit cards are not widely accepted and invariably payment is processed using the paper slips, often with an additional charge of 3-4%.
How much you will need for shopping is difficult to predict, but most people buy more than they plan to. If you want to buy quality art works including hand-painted thangkas, carpets or traditional jewelry you can easily spend USD200+ for top quality items.