RULE OF THUM
Any item 4/10 and below has structural damage or damage that will strictly Hinder the performance of the gear.
Any Item 5/10 or 6/10 gas been used for many seasons or has been put to the test hard in one season this item may have moderate abrasions that are noticeable but do not pose sever threat of faulty gear.
Now to the real part
Any Item that is rated 7/10 - 8/0 should have little wear just from use and should not pose any threat of damage to hinder performance.
Any Item rated 9/10 could have been worn very minimally, could be washed but have no rips, stains and stretch marks.
Ant Item rated 10/10 should have not been worn other than trying on, should still have tags on it and have not had any change to it the way that it came.
I am only here to help the avid NS buyer and encourage the seller to follow these guide lines in order for a pleasant purchase.