TRAP:If your landlord or sublessor refuses to give you a signed Wohnungsgeberbestätigung, they are probably subletting illegally. Without this document you cannot register your address, leaving you without a tax ID or bank account. Also, pay attention to the religion question on the form: writing Catholic or Protestant will trigger an automatic 8% to 9% church tax on your salary.

TRAP:If your entry visa expires and you have no written proof of an active application (such as a Fiktionsbescheinigung or an official confirmation email under § 81 AufenthG), your legal right to work stops immediately. HR has to suspend you without pay until your status is resolved.