I have been buying used LP's off the bay for about three years, and am generally pleased with the experience.
Out of approximately 80 LP's:
2 were warped (Asia debut, and On Your Knees by Great White)
1 was defective from manufacturing (90125 by YES was one of the club editions mentioned below, and it was mastered too fast)
3 were not as described: (Julie London's Lonely Girl and Calendar Girl, and Bob Seger's Against The Wind)
2 Japanese pressings were poor quality stampings (distortion and extremely low treble): Prologue by Renaissance, and Evolution by Journey
2 were record club editions. Mostly my fault, as it was clearly evident in the photos, but not mentioned in description.
All the others were either as I expected or better.
I do have a pretty low standard for the condition of the jacket of a used LP, although I can't stand creases from bending.
While shopping for used records, you have to apply a different standard than you would buying new.
Even though the seller claims the 60-year-old record is in mint or near-mint condition, that is just too improbable, given the
common handling and storage techniques. You can't expect much, but it should still be a fine specimen that is very listenable.