I don't even care if their coins are over-graded, as long as they can be re-sold for a reasonable portion of their purchase price, so I don't lose tons of money. I collect for fun, not to make money, and don't mind if I lose a little money, but I still don't like to be robbed. I have a limited budget, and try to keep my purchases less than $500. My interests lie in type coins. So who do you trust?
Some well known established and trustworthy online dealers recommended for type coins: JJ teaparty Mark Feld Typecoin (ebay)
I recommend, http://www.empirecoins.net , I've done business with them for years with zero complaints...