I'm wondering whether to exchange for 200 or 300 euros at the airport in DFW before leaving, or wait and get them once we arrive at CDG airport, or get them at an ATM outside the airport, etc. I'm not sure about the best exchange rates, the safety of having the cash out of the money belt to make the transaction, or just how quickly we'll need the correct cash once we get there. For instance, we'll probably have to pay for the shuttle from the airport to Paris in cash euros.
Diane, if you don't want to depend on ATMs right after arrival, which is understandable, the rule of thumb is that you get a better deal exchanging cash in the country of destination. Again, it's just a rule of thumb. Maybe you could monitor the exchange rates of the banks that provide ATMs at CDG airport and the ones at DFW online? Keep in mind that in addition to the hidden charges there will most certainly also be some kind of service fee.
My advice is to do what we did. Pull cash from ATM and go directly to a bathroom and put some in money belt.
We had a cooking class for two the day after we arrived in Florence. We needed to be equipped with 468 Euro. We were concerned so we went to Wells Fargo here in the U.S. and got 500 Euro. Our daughter works for the bank so we got an exchange rate of 1.39 (market was 1.345). Their regular exchange rate was 1.43. We paid a 3% hit. The regular hit is 5%. It's a bit higher than simply using your ATM card when you reach Europe. And, that's if you find an ATM at the airport. We had this great plan of finding an ATM in Frankfurt (our transfer point) but there were none inside our secure areas of the terminal. We did get ATM cash the next day but we were limited to 200 Euro. We were fine because we had our cash for the cooking class. Your plan to use the ATM once you get to Paris looks better than ours as you will be exiting the airport and you should find ATMs on your way out or nearby. The ultimate hurt is to buy Euros at one of the money exchange places in the airport. Up to a 10%-15% hit.