Currency Strategies?

Since we will be traveling in four different counties, only one of which has Euros as it’s main currency, I’m wondering what you all are planning to do? I was going to try to operate entirely in Euros, but I just talked with RS and it seems like a better idea to get some Euros when I land in Amsterdam, but to wait and get local currency at an atm in Poland, Hungary, and the Czech Republic. What do you all think?