I am choosing the best way to exchange money for my travel to Serbia (Kopaonik region, going for skiing). As long as bank cards are not widely accepted there, and my bank charges 1% for withdrawal in ATMs of other banks, I'm going to bring most money in cash, and exchange locally to dinars.
Which of the currencies (USD, EUR, Russian roubles) have the smallest spread (buy vs sell ratio) in the exchange offices available in rural areas like Kopaonik? In Belgrade airport?
(we'll be transferring from the airport directly to Kopaonik, so no major cities to consider for our trip)