You need a bit of luck buying a lens from an unknown seller as another way of looking at is:- That well used lens could be from an ex pro who had an excellent copy and used it a lot (because it was so good) or could be from Joe Bloggs who abused it (even a drop say on the lens cap, that could be replaced, could shift the lens elements if unlucky) . Same for a mint lens, it could be mint cos it was a crappy copy and not used much and would be glad to pass it on. There is some truth in... all the best copies of lenses owners keep and all the rest go onto the bay.
So the shots and crop are from my mint 50 mm, and I'll never know if you could get sharper results unless when I took the the shots there was another guy with me with the same setup and we compared the results , or I could buy about three 50mm lenses do test shoots pick the best one and sell the rest.
Good luck buying your lens of choice.
No one mentions Fuji pro 400h and it shows at least it's VG for scenery..but it's expensive at about £11 plus for 35mm or 120. I always thought pro films should be used immediately but the film I used could be about 12 years old...half the time stored at room temp and other half in the freezer.