Look in my eyes. Look - look in my eyes. You know me. Do you see anything in these eyes that would let someone take advantage of you? You know that'll never happen. So listen to me when I say...
DON'T EVER EXCHANGE YOUR MONEY AT A CURRENCY EXCHANGE.
Just don't do it. These companies survive by making money off tourists. There's literally nothing worse, except maybe that one friend who likes to move in slow motion when it comes time to split the bill. I had a friend who worked for a currency exchange in NYC that was so conflicted with guilt that she quit her job after a few months. They are taking your hard earned money.
HOW THESE CURRENCY EXCHANGES WORK
A. charge you a service fee that is a percentage of how much you are exchanging
B. Increase the exchange rate to their favor so that they're charging you more on top of the service fee
So you're getting charged twice. That's why they're always in tourist spots + airports. Once you're in a new country, it will be hard to distinguish counterfeit bills.
WHAT YOU SHOULD DO
Rely on your OWN bank. You are their customer + they will treat you best. If you have some time before you leave, go to your bank and get your money exchanged. Often, your bank can have the currency delivered to the location within a few days. I know Chase does this for free.
Personally, for me, since I was backpacking, I never felt comfortable carrying a boatload of cash with me so I relied on my ATM card a lot. You get the best exchange rate abroad when you use the ATM card because you'll actually be getting the market rate that day from your bank. There are often fees so here's the rundown of how I was able to spend without getting charged.
First off, make sure you have 2 debit cards from 2 different banks.
This way, if your bank for some reason declines you - you'll be able to get money from the other account. Also- never ever keep both cards in the same wallet or place. I would always keep my cards separate from one another, one with me and the other locked in my luggage at the hostel/hotel. Also hide $100 USD emergency cash throughout various places in your luggage.
I used Chase and it charged me $5.00 each time I used the ATM abroad. In Colombia it was also difficult to use the ATM because my card didn't have a chip, which most other countries use. I rarely ran into problems in both SA or Europe despite not having a chip in my debit card. Afterwards, I learned of the Charles Schwab Online Banking Account that has no minimum, works worldwide, and has no foreign transaction fees but also REFUNDS YOUR ATM FEES at the end of every month. I don't want to tell you how much my ATM fees came out to- but it was a lot. So, for my next trip, I would definitely recommend getting one.
Also, Chase is now offering the chip with the ATM cards now, so go look into it!