Help with 1917 Erfurt Luger.

[DavidJayUden]

I can't tell you much from the photos, but it would appear to have been reblued, which will hurt its collector value.
In the USA we would call this a shooter grade gun because of the re-finish job, and such a gun would sell for somewhere between $750 and $1000.
Hope that this helps, and more and clearer pictures may get you more information.
dju