Relocation costs

Hi all, I was wondering whether you could help me with the following. I'm relocating (back) to Germany in a few months, to a 5-year postdoc position. I would really like to have some support to cover relocation costs, but apparently in Germany those are generally only covered for new professors. But it seems like there might still be some grounds for negotiations (with the faculty, or with 3rd party funders) -- does anyone have experience with that? I feel like I shouldn't just accept that they won't cover (part of) my relocation costs, when I'm specifically invited to take on that position.