"He got it graded and turned around and sold it for $5500!! That’s a tremendous difference. All he paid me was $15 bucks"
The service you did that guy, he really could have paid you more than $15. Unless there's another guy just down the street keeping prices at a fixed $15, you really should consider raising your fee.
Cos judging by those two examples above, it's an excellent service you're providing! :)
Well there is kinda a standard pricing in the industry. Usually $15-$20 ish. On a much more evpensive book it can get pricier though.