LSMorgan, wow thanks for that great answer.
I have maybe a $300 error coin (copper wash nickle), I was thinking about selling it on ebay. It just feels like the coin graders have made themselves quite the guild, I smacks a bit of shutting out the little guy that only wants a coin or two graded. I don't mind paying the price for grading/slabbing but I dislike joining the club to send the coins in on my own for grading.
Read this yesterday:
http://en.wikipedia.org/wiki/Coin_grading
In the May 26, 2003 edition of Coin World, the hobby newspaper had announced they had contracted investigators to conduct a year-long, comparative study of PCGS, ANACS, NGC, and ICG, along with several other grading services, each known as a TPG or Third Party Grader. In their investigation, Coin World sent several of the same coins to each grading service over the course of a year, each coin being graded by all Third Party Graders sent to. The findings were; "In no case did the grading services agree on the grade of any given coin, and in some cases the difference in grading was as much as seven points off". By way of example, a finding published by Coin World involved one case where ACCGS had graded a coin as "cleaned", which lowers the coin value. Additionally the coin had been graded several grades lower than PCGS while PCGS had not noted the same coin was "in fact, cleaned". It is standard in U.S. numismatics to grade coins on a point-scale from 1 (poor) to 70 (perfect), and to note if a coin has been cleaned or poorly mishandled, or in some cases to reject it for encapsulation.
On January 5, 2007, the Professional Numismatists Guild (PNG) published a more recent report about grading services and standards. The survey indicated the professional opinions of numismatists who buy and sell coins. No grading service was listed as "outstanding". PCGS and NGC were ranked as "superior". ANACS and ICG were ranked as "good".