In border areas such as in this case in the DE / LU / BE region, the standard procedures typically applied within the federal territory cannot be applied universally. In a case like this, living in Germany and working in LU, for example, it means that direct banks like Ing-Diba reject directly and have no interest (this could be due, among other things, to the fact that wage garnishments are not as easy to implement as in DE). However, if you go to the local Sparkasse or Volksbank in Trier, you will be very warmly welcomed there. The background to this is that banks in the border region have no problem with such constellations at all, and the financing amounts for cross-border commuters are on average somewhat higher. So if a financial broker, then it is probably better to inquire at the local offices of the two most well-known ones, or directly at the banks on site. Or even consider Luxembourg banks, whereby financing here is mostly chosen with a flexible loan (without fixed interest rate), which is alarming high for us Germans.