One important thing to know while shopping in Athens, especially at the tourist places is that no price is the final price! When shopping, it is not considered rude to barter and negotiate prices (politely). I recommend doing this especially if you are purchasing a few items or paying with cash. Usually, the shop owner will give you a lower price if you are buying more things. Remember to always be polite when bartering and know that you shouldn't go too low, people should still be paid fairly.