Turk Lirasi(Turkish Lira) has many zeros in use but the currency changed on 1 Jan 2005.The new money is Yeni Turk Lirasi(New Turkish Lira) and 6 zeros is thrown out. The currency of YTL is about:
$/YTL = 1,30,
€/YTL = 1,80
There are many Change offices.You can also exchange money from Post offices and banks.
Major credit cards (Visa,Mastercard) can be used in most of the shops in big cities. But you should have some cash with you in case of absence of POS machines.
You should tip the waiter. 1 or 2 YTL is enough for small receipt.But for big receipts the tip should be not less than 5 YTL
You should bargain in most shops.Since you are a tourist you have the right to bargain. Wait until you get the "last price" of the seller.
Depends on the thing you want to buy.Quality items are logically more expensive then disqualified.But Turkey is a cheap country and you can find anything at any price..
For more you should contact me