BBVA Ajijic ATM's

Always, always, always choose to be charged in the local currency of the country you're in. If a Spanish ATM asks if you want to be charged in GBP, say no. Don't let the machine do your currency conversion.

Here's why you shouldn't let an ATM do conversion for you:
Foreign ATMs and card machines often say nice things like: This ATM offers conversion to your home currency.

On the surface, that seems pretty generous. It looks like you'll know exactly what you're paying, and in amounts you're way more familiar with.

Nice, right?

But, in reality, paying in your home currency is hidden-fee-hell.

It's a scam that goes by the name of Dynamic Currency Conversion (DCC). DCC means you effectively ask a foreign ATM provider or bank to gleefully make up an exchange rate for you. And the only thing more likely to screw you over than your bank, is a foreign bank.

This isn't a kind-hearted service. It's something banks use to take more of your money without you knowing.