We keep grading simple: three tiers. Most opened bulk is Near Mint or Lightly Played, our top tier. Sleeved-and-played or visibly worn cards are Moderately Played, and anything creased or damaged is Heavily Played. Yes, we still buy all three.
Look for whitening at a 30° angle under bright light. That's how we grade.
For bulk, don't over-grade. Most quotes assume LP/NM mix and we adjust on arrival.
A single deep scratch drops a card from NM to MP. Those are the hits we look for first.
Slight off-centring isn't condition; it's a print defect. Doesn't affect bulk pricing.