Chemists are kinda particular about what qualifies as "used" when it comes to glassware. If it's been used for anything, even to hold water, they consider it dirty. Basically, if they weren't the one to open the box on a new item, they don't trust its history.

Good luck with the sales, but don't expect anything near top dollar on the glassware, and probably the crucibles and anything that would come into direct contact with an experimental chemical.