1917 DWM - New Owner Questions

[Chatelain]

Hello, this is my first post on this forum, and I was hoping for a little insight on my recent acquisition. Several weeks ago, I inherited two handguns from my Grandfather - a '92 Colt 1991 and a 1917 Luger P08. I'm pretty familiar with the Colt, but my knowledge of the Luger is very limited. I'm hoping that you fine folks can help me out with that!

From the research I've done, I've determined (and been told) that I have a genuine 1917 German-made 9mm Luger that has mostly matching numbers. And, well, that's about all I know, aside from the basic history of the P08. Hopefully someone can answer a few questions for me.

Not that I would ever sell this gun (since it is a heirloom), but approximately how much is this gun worth? I've taken it to a local firearms dealer, and the gentleman there told me it was in good shape and, after a thorough cleaning, ready to take to the range.

Is it common to find any hand-etching on these guns? Seems like this may have been a military or police thing since it surely decreases the value.

What's the best way to clean the grips without ruining the wood or checkering? They seem pretty filthy.

What is "Miltex, Inc."? I'm assuming this is some sort of business specializing in import or military firearms...

Last question. The take down lever is VERY difficult to move. I cannot move it with my finger, and have to use a flat, dull tool to drop it down. Is there anything I can do about this?

I've included a bunch of pictures for your viewing pleasure. Thank you all in advance for any advice you have to offer!