In ending the listing, the seller made it so you will lose ebay buyer protection since you won't be buying through ebay. And in doing so, the seller is cheating ebay out of the fees (10% of the total payment amount) ebay rightly earned by giving her the exposure allowing you to find and buy the item.
If I were you, I'd have her relist it so you can buy through ebay.
if the seller won't relist on ebay and if you buy privately, make sure the payment is for "goods" and that you do NOT purchase as friends and family. (F&F offers no protection for you.)
ETA: I'm curious to see how the authentication goes. Call me cynical but it was NOT necessary for the seller to end the listing early in order for you to have it authenticated. I have little doubt she did that to save herself the $1800 FVF fee and IMO, that's cheating.
http://forum.purseblog.com/authenti...e-read-the-rules-821115-635.html#post30233423
ETA again: This one is important!! See my post which follows your authentication request.