After completing my PhD in the Netherlands, I came to Warsaw, Poland, for a postdoc position at the Institute of Mathematics of the Polish Academy of Sciences. Since I am a European citizen, securing a visa for myself was not a problem. However, my fiancée is from the United States and it was much more of a fuss to obtain a residence permit for her, mainly because we are not yet married. We were in the process of going through all the paperwork and trying to figure out how to proceed when someone recommended that we contact Monika Zaremba from EURAXESS Centre in Warsaw. I am extremely glad that we did because from the moment we contacted her she took complete control of the process and helped us with every part of it (filling out the application forms and accompanying us to the appointments and to a tax office, including having one of her colleagues come along as an additional translator); she supported us in every step of the application process.
I am sure that without the help of EURAXESS it would've been very difficult for us to apply correctly for the residence permit, and perhaps the result wouldn't have been the same (we ended up getting the residence permit).