Nickel or Chrome Plated

[zeke1312]

OK, novice questions but I wanted to make sure my understanding was correct.

1. There were never any Lugers ever manufactured from any licensed source that were chrome or Nickel plated. All such guns are done by or for their owner and mainly done in the US.
2. Some cautions to look for (generally speaking) are:
A. So called "papers" with a Luger. Are they real?
B. Guns with their holster and cleaning tool add to their value.
C. Lugers with matching S/N obviously more valuable.
E. The comment "it was re-blued, chromed or nickle plated
was because there were blood stains on the gun" (sounds
really suspect to me).
I know there are other things to look for but tell me, are my assumptions correct? What exceptions to the items I've listed are there? Is this not a true statement: When Lugers were initially brought back from WWII their true value was not realized?
Thank you