Had to check it out for myself. I would be afraid to buy anything that paris had had her hands on who know where it has been and what you could catch from it! The post says that she is her CLOSET ORGANISER not her stylist, BTW. Wouldn't that be nice to have!
Honestly, I've never met her. All I know is that I've done great business with her in the past and she has a wonderful reputation for selling authentic merchandise. I don't have any reason to doubt what she says about where her items come from. As I said before, she has sold many items from other celebs and I don't see where her selling Paris Hilton's items are any different.
Most of the items the seller says have been used only once. I guess it depends how much it's been used once. If it comes from a celeb known for partying and not caring about the stuff, it could be a pretty used item even if only used once.