There's some sort of crud visible at the edge of the front element from roughly 6 o'clock to 9 o'clock. Might be oil, might be coating damage. If oil, a microfiber cloth and Super Kote or maybe R.O.R. lens cleaning fluid might remove it. If coating damage, negligible.
I can't tell what's going on with the rear element's outer surface. Whoever took the pictures want to learn how to photograph lenses.
If the lens' price is low enough, gamble. If too high or you're very risk averse, don't get it. It is, though, much cleaner than most of the ones I've seen on offer.