Need some help

[Herb]

Gentlemen I am at a loss on this one, I haven't paid much attention to this model as I never really expected to find one. Actually this is the first one I have ever seen. Today I inspected a Luger that is for sale as a result of an ad I placed in the regional paper. It turned out to be a 1900 Commercial. I need your thoughts on buying it. The particulars--it has been heavily buffed and reblued, there is still some evidence of past pitting that didn't get buffed out, blueing is excellent though and straw is about 90% less the thumb safety lever that has been blued. Serial number is 4771 and all numbered parts match and are in the commercial fashion. The chamber is unmarked, the toggles are the dished type and the toggle lock is present on the right side. It is DWM manufacture, and 30 cal. and the barrel is 4 3/4 inches and has the slim taper. The grip safety is present and there is no stock lug. Left grip cracked on the upper forward part but repaired, right grip appears to be a replacement, magazine appears to be a Mecgar type. The extractor is the old flat type as is the main spring and the firing pin is the old model. Here's where I need some help as these are so hard to come by, what are your best estimates on it's value in the condition I have described??