Law / VoIP Business in Poland [17]

Virtual Phone number and local phone number will work with VOIP service.
ringcentral.co.uk/how-it-works/local-numbers-availability.html

Life / Is there a way to call someone and with hold your number in Poland? [10]

With holding a number barely depends on your network provider. codes are used to get your line secure from unwanted calls.

Life / Polish prank phone calls [5]

Prank calls are very annoying. Prank callers really enjoys when the person on the other line is pissed off. Having a call screening service on the other hand limits unwanted calls.