The average salary in Warsaw (highest in Poland) is 6k PLN. Google (as any reasonable IT company) will pay no less than 20k PLN for senior developers. I would say that it's a pretty good salary even for Warsaw standards...
Of course, B2B contracts are event better, mostly because of lower taxes but they have their own disadvantages (often they can be terminated within a week, you don't have PTOs etc.)
Not that much less, and the cost of living is geared towards someone making a tenth of what you make.
I find I'm saving more than when I was living in a western country.
Of course, B2B contracts are event better, mostly because of lower taxes but they have their own disadvantages (often they can be terminated within a week, you don't have PTOs etc.)