Currency Regulation :
Limits : There is no limit on the amount of foreign currency that may be brought in to Turkey, but more than $ 5,000 worth of Turkish currency may be brought in to or taken out of the country.
Exchange slips : The exchange slips for the conversion of foreign currency in to Turkish lira should be kept, since you may be required to show these when reconverting your Turkish lira back in to foreign currency, and when taking souvenirs out of the country (to prove that they have been purchased with legally exchanged foreign currency).
