[perseiden]

Speaking of bureaucracy, one thing that shouldn't be left out is that as a non-EU citizen you will also have to deal with the Ausländerbehörde for your visa. There you will have to deal with bureaucrats that refuse to speak anything besides german and the rather complicated process of acquiring a visa or specifically an Arbeitserlaubnis that allows you to earn money. My wife had to go through it as an employee and I've helped colleagues with visiting scientist visas. I've heard from others that a freelancer visa comes with a whole array of different requirements that can be hard to meet, but maybe someone else knows more about it. While visas here in general are doable and probably a lot less complicated than a US Greencard / Visa, it is something you should check out beforehand.