That back issue trick from the guy at my LCS paid off big
A collector in Tulsa told me to check the 25 cent bins for damaged copies, found a first printing with a crease that graded a 9.0 after pressing. Cost me $12 total with supplies, flipping it for $85 on eBay. Anyone else find steals that way?
That "pressing" part is doing a lot of work in your math, since a crease doesn't just vanish, it gets flattened and graders can still flag it as color break. Glad it worked out, but a 9.0 on a book with a visible crease is the exception, not the rule.