Get informed about Poland and Poles and you'll realize that your question can shock....
Why should he care about that ? Apparently he's trying to figure out how much of it he could save... Let's say you got offered a job somewhere in the Gulf for EUR 50k a year... Now is it good money or not ? You need to know what are the costs of living there...
No Pole with the language and connections gets this kind of salary!
Huh ? 10, 12 or even 15k gross are nothing so unusual for senior specialists, I remember some thread (lost track of it somehow...) recently with a Danish guy claiming to be 25 years old and making 30k gross or something in 3 city, that was strange, but 10k a month is not... get a job at HQ of any mid-large company, push 1 level up from the bottom and that's it.
I believe most of those jobs could be filled in by Poles.
Well it seems like these are technical IT jobs and evidently the Poles are either unable or unwilling to do them at this price.
These are corpo jobs and corpos are ineffective by default, people at the bottom can't decide about anything and people at the top are out of touch with anything on the ground... In cases like this, I guess HR dept prepared requirements for the job and that includes let's say "3 years of experience in working with (insert some rare shyt, like some software that's unknown outside let's say a narrow circle of corporate credit risk modelling people)" and that's it, it doesn't matter that typical IT guy could learn it within 3 months and then work with it for half of that money. They need someone "with experience" and that's it and in case of niche things, there really might to be a problem to find someone available in Poland, while Indians, there's over a billion of them.