The first time I went in I paid thirteen carriers to haul my supplies, packed in cardboard boxes and trunks, the twenty miles from Bundi mission to Yandera village. It was a nightmare for all concerned, although everything I brought was necessary to my work, comfort and safety during a year's fieldwork. Any major bank in the United States can arrange for you to get foreign currency. You can also get money exchanged in airports although the best exchange rates are in local banks. You will need a small amount to carry into the country for taxis or other small and immediate expenses.
Many banks have branch offices in small towns and some rural stations.
It is important to build up your physical strength and stamina before going to the field by hiking and exercise such as step aerobics and climbing stairs. You should also quit smoking. During my first fieldtrip I learned to forgo smoking for two or three days before a long hike to increase my oxygen intake. After I quit smoking in 1990 I was amazed at how much easier it was to climb mountains, in spite of being twelve years older in 1994.