A friend of mine lost 50 lira to a taxi driver. She took two 50 lira (about € 25,-) notes from an ATM, then paid the taxi driver with one of them. He said she only paid 5 lira, and showed her a 5 lira note. She believed the guy, since the 5 lira note and the 50 lira note are both yellowish and you can easily mix them up. My friend apologized and paid again with the other 50 lira note. Later it turned out the bastard taxi driver had swapped the 50 lira note with a 5 lira note and showed that to her to convince her she paid the wrong amount. So that’s how easily you can spend money in İstanbul, so to speak. My advice: don’t pay for a taxi with 50 lira note, or if you do, when you hand over the note say out loud: “See, it’s 50 lira, do we agree on that?” Spread the word!