If you are intending to sell your property in Turkey within five years after purchasing your property, you can pay capital gains tax in Turkey, if you made profit on this property.

If you purchased your property over 5 years and kept on your name on the title deed full 5 years of period you will be exempt of tax.

But, if you are involved in property trade ( meaning you keep buying and selling properties in Turkey, every year min. 1 property, and you have been doing it at least 2 adjecent years, that means you are property trader according to law, eventhough you were not legally registered property trader at the tax office in Turkey) capital gains tax apply. 

The capital gains tax required is worked out as a percentage of the profit you made on the property.
In other words the difference between the figure declared on your title deed when you brought the property and the sales (agreed) price that will be declared at the Land Registry Office on completion of the sale.

So we reccomend to declare you the right amounth of figure when you are buying your property even it is possible to declare less amounth according to Local Councel valuations.