False Return, How do Returns Work for Sellers?

So today, after numerous successful shipments through Offerup shipping, I got my first return. The buyer claims that the Coach bag I sent her is fake, but of course I have authenticated Coach bags for years and I am 100% sure that the bag is absolutely real. They paid $20 for the item plus $8 shipping. This buyer got moody when I didn't ship on Sunday (what?) and has been a pain to deal with overall. The buyer has submitted no evidence that the bag is fake and just simply states that the handles on the bag and material are "red flags", without showing me any actual factors of authenticity. They are talking in all caps and being quite disrespectful in manner. All that aside, I have four questions about this: 


1: How does Offerup protect sellers from buyers that make false claims without proof? I can list several factors that prove the bag to be genuine, but is it just the buyers word against mine?


2: Does this mean that I will lose out on the shipping cost? Will I have to pay the $8 spent on shipping out of pocket to give the buyer back the total, or does Offerup somehow not charge that?


3: Does Offerup credit the fees deducted from the total? It wasn't very much money, as they only paid $20 for the item itself, but I'm just curious. 


4: Can the buyer leave one-star ratings on a return? I have enough good ratings that I doubt it would impact my 5-star rating, but I'm still concerned about how that works.


If anybody could answer these questions for me that would be much appreciated. Thank you!

Community Helper
Okay... @MarianaIslands
Let me see what I can assist you with, and possibly other members will chime in... with their OU knowledge.

1. OU has a Buyer Protection protocal they follow. Believe, after a claim number is issued, you will be given instructions on how to pursue this fictitious claim. Possibly even having to ship the item to OfferUp HQ, for authenticity confirmation?

2./3. These inquiries would be best addressed by a Super Shipper, @RevivalGypsy Smiley Wink

4.That is a possibility, but they can only rate you, if you rate them first. Since you are the Seller, that is up to you, to mark the item "Sold to someone else," and not receive the possibly, low star rating. Or rate them, and not be too concerned, since you are already well established, with a 5-star rating.

GLTU! Ciao´ for now...