Pulley System

I'm calling B.S. on this- how can you have a price for a system, or be looking for pulleys if you don't even know if it's a V8 or a slant?? Two different animals, and not even remotely interchangeable.
I'm well aware of this, but what's wrong with being prepared? If it's a V/8 car I want to be able to be on it quick and if I have my information ahead of time I'll have something to bargain with. I even said this at beginning of this thread that I wasn't trying to jump the gun. With the car being as clean as it appears and if it does have V/8 along with its price it won't last long and I want to know what a ac system would cost me. Understand