Grading Of Overprint Stamps

How a overprint stamp is evaluate. Does an otherwise very fine stamp lose value because it does not have a clean overprint?

This is a complex question.
Overprints can be more valuable then originals regardless of quality.
Actual demand and scarcity are often the driving forces behind value.
Forged & unauthorized overprints can still even draw greater value depending on who was behind the overprint.
Some forgeries can be of better quality then the originals they are mimicking.

Was there something you have that brought you to asked this question?
If so, can you scan & post it here, we can help?

Mike

Warrehouse,

How funny I work in a wharehouse... Thank you answering, it's the first topic I post. I bought an iceland stamp last week at a dealer Scott 67 used. Centering is not bad but overprint is not clean or precise. Anyway I paid way below Scott cat value, about 40 %. Back home I checked ebay a fixed price for 66, 67, 68 that the overprint look better than mine and a good price too. I just feel I made a bad move last thursday, but I like once in while to buy at the dealer to give them a little business and keep them alive. Yes it's about time I get a scan. Could be today. Daniel