i wanted to do the exact same thing with my 145.
but its costly.
i spoke to some people who were willing to fit the air con unit, and they were saying around £800, cos they have to take of the whole dash.
your in turkey so it may be worth it 4 u, but im in england and the summers in this country last all of 2 weeks.so i didnt bother.
its much cheaper and effective, to roll down the huge windows alfa designed and drive fast!