There are too many sellers with misleading thread titles. Everybody's like "10 - 15% fee!" and then when you go into the thread, they're actually asking 20 - 30%. Or they keep bumping the thread advertising 10 - 15%, but then they send you a link to their Dis.cord or Tele.gram and ask for their inflated fees there.
And then there are the ones who try to fuck you in exchange rate. 10% means 10%, not 10% USD when the order was in a weaker currency like CAD/AUD.