What is the cheapest place or way to change your money when in crete i will be staying in stalis??

Its all personal preference.

Most would advise that you dont travel with large demoniations to change, lose it and you have lost the lot!

Many would stick to the old card at the ATM or use of 100 Euro or so to "get you in" and the rest in Travellers Cheques which if lost or stolen are replaced. Many opt for a combination of Euro, Travellers Cheques and plastic.

Whatever you do shop around for the best rate.

To be honest there's not much difference anywhere some look like they give a good exchange but charge commission and others seem to have a lower rate but don't charge commission you're just talking pennies and it's not worth the hassle of traipsing around.
Rick

from my experience the banks charge a flat commission regardless the amount of money where as the tourism offices work on %. so for me its a matter of how many pounds to euros you would like to change and to find what is best for you when there after shopping around the commissions

The post office always used to give a good deal compared to any of the banks. I always use an ATM nowadays.