Thank you, where can I find real prices of these coins? I found this website: http://www.coinstudy.com/mercury-dime-values.html, but prices are much more lower.
What do you mean by "real" prices? There is no "fixed" price on coins (aside from face value), they are worth whatever someone is willing to pay. I would check ebay completed listings to get an idea of what your coins have been going for recently.
OK, here it is on the Red Book:$12 for the 1917 $40 for the 1918P $50 for the 1918D and $40 for the 1918S, assuming they are all AU. For the 1918S which looks like it has hopes for a low MS jumps to $120 in MS60.
Someone want to sell it for $15 for all. This is why I had this stupid questions. I think it is good deal.
No prob. I have company here on cointalk during nighttime( in Korea) I try to say something to every post.