You are introduced for the 1st time to someone. What do you say?
«Χαίρω πολύ» is the neutral response that is suitable for both formal and informal situations which is something like “nice to meet you” in English.
Nowadays, it is really common amongst friends, to just answer with a simple «γεια σου» or γεια σας» if you are introduced to more than one person.
At the end of your meeting you would say «χάρηκα» which is something like “it was a pleasure meeting you”.
So, let’s sum it up!
Χαίρω πολύ! = nice to meet you
Χάρηκα (πολύ) = it was a pleasure