Work / Job offer in IT company in Krakow Poland. Would 7000PLN net salary be too much? [5]

Hello

I got a job offer at an IT Company in Krakow and they are asking me to propose them what salary i want but i really don't know what amount i should tell them. Could somebody help me please. Would 7000PLN net salary be too much to ask? Or what basis should i negociate my salary with the company because i don't know much about the cost of living. Its been one year i have not been to poland.

Thank you everyone in advance for your help.