A few questions for the group.

I want to save the fees associated with exchanging currency at a bank. Is it possible to arrange to buy Euros from a traveler, say, at the airport as I am arriving or departing?

Does it make any sense? Will the traveler and I be able to save money by avoiding the fees?

I assume that it is black market, possibly illegal, but I know that travelers to South America readily exchange dollars for local currency at a much better rate than the posted exchange rate.

Are there any resources online about this?

Thank you in advance for any information.