I'm looking at a 1909 VDB that is MS grade, but the shop is asking about twice the what the red book is saying. It has a red brown patina. I Haven't been able to find much online on how much the red brown effects the value. Any advice?
A RB coin does command a slight premium compared to it's BN counterpart. And, I don't know that I would use the Red Book as a price guide in that case. I would suggest searching eBay for coins sold in the same condition (including the modifier of RB - assuming that the coin you are looking at would be considered RB). This should give you a decent comparison.