The Nepali rupee(Rs) is divided into 100 paisa(p). There are coins for denominations of 1, 2, 5 and 10 rupees, and banknotes in denominations of 1, 2, 5, 10, 20, 25, 50, 100, 500 and 1000 rupees. In some major cities that will allow you to retrieve cash from ATM or credit cards, but you may be charged a service fee. Away from major centres, changing a Rs 1000 note can be difficult, so it is always a good idea to keep a stash of small-denomination notes. Although Indian currency is valid in Nepal, the Rs. 500 and Rs. 1000 currency notes are not acceptable.
Tipping is a newly accepted custom in Nepal. Hotel, restaurant, touring and trekking organization staff members often make up for relatively meager wages with tips. But, it should only reward good work. Don't tip for short taxi rides in town or any service person you've bargain with. Groups might give a reasonable amount per day to a tip pool to be divided among the staff, generally relative to rank, for good service.
No tax refund for shopping in Nepal. But for airport tax, the Tribhuvan International Airport Tax is NRs1356 to SAARC countries and NRs1695 to all other International destinations. Airport Tax for Domestic departures is NRs200. Nepalese going to SAARC countries are requested to pay NRs971 and NRs1130 to all International destinations.