Cost of Polish lessons, courses (private)

I already said about tunnelling, you can read about it on wikipedia.

en.wikipedia.org/wiki/Skype_protocol

"Skype also routes calls through other Skype peers on the network"

do you know a good school for polish in krakow?

one with skype is the cheapest one.

It all depends. I was learning with a professional tutor for 80pln. Before, I had lessons with a student for 30pln.
It was a big difference.