How to say these in Turkish:

1. How much is this for?

2. Okay, I will have this.

3. I know how to speak Turkish.

Çok teşekkürler! İyi geceler..

Ne kadar? How much? (implies this)

Bu kaç para? How much is this?

Tamam, bunu istiyorum. Literally: Okay, I want this.

Türkçe konuşmayı biliyorum. (I´m not sure if this is correct?) I know how to speak Turkish

Türkçe konuşabilirim. I can speak Turkish.

While all of what denizli said are correct, I felt the need to add some other that are more frequently used in daily life.

1. Bu kaça? Kaça bu? Bu ne kadar? Ne kadara bu? (As you might see our syntax is -quite- flexible. ^^)

2. Tamam/Oldu, bunu alıyorum/alacağım. ("Oldu" means "alright" in familiar language and it´s quite a popular word.)

3. Türkçe biliyorum. (Oddly, we almost never say "I speak a language" but rather say "I know a language".)

"Türkçe konuşmayı biliyorum." is correct and quite acceptable. However "Türkçe biliyorum." is more often used.

Hope it was helpful,

-Jansay

Thankyou Jansay!