That is a rare DWM 1906 Grip Safety Luger. In nice shape it would be valued at around $3,000 bucks. This gun has been badly damaged by having the finish buffed off. Some one ruined it by cleaning off the original finish and did a very poor job. It may bring $600 on a good day.
If it were mine I would have it rebuilt by a German Arms company that specialize in saving these guns. I would expect to pay about $1,000 dollars to have this done.