Feedback is useless for sellers.

[nightshopper9999]

One can not leave neutral or negative feedback for buyers that woefully deserve it.  Don't try leaving positive feedback with a negative comment because the buyer can just have it removed. The feedback system is not a true metric of the buyer.

  The buyer direct messaged me comments like this...." I will go out of my way to make you pay even more by making sure everybody that looks at your feedback will go elsewhere"  and " It doesn't matter to me what you think because now everyone that looks at your feedback will shop elsewhere before even considering giving money to you and that will cost you even more money in the long run" and "  I haven't even begun to be a harassing to you, wait till you see what kind of person I can really be!"  

Be warned, the buyers' feedback are a lie.

[2nd-time-around-jewelry]

You need to report the buyer especially if they have harassed you through the eBay messages. Phone customer service. They can see your correspondence with this buyer & may even remove his negative comments from your feedback.

[femmefan1946]

"420" would be if not a red flag a pinkish one.

And with ten negs and a neutral in his past 100 feedbacks! Wow! And in less than six months!

Put him on your Blocked Bidders List immediately.

If there was an Unpaid Item Dispute and you won, he got a Stirke. 

You can Block bidders with Strikes from your Seller Preferences/Buyer Requirements.

If a member gets "enough" Strikes, eBay will close his account.

I agree that you should call Customer Service during weekday business hours with those Messages. Also refer to his Feedback Left for Others.

BTW- You can refuse Returns but you cannot refuse Refunds.

Was this the beginning of the argument?

[esclyons]

sounds like you got an extortion email,, so if anything negative was left for you, and or it  was not good, get ebay to remove it,, then block this person,, unfortunately that is all you can do as a seller..

[ichopshop]

420 does certainly seem to have more than his share of negative interaction with sellers.

I wanted to see if I'd left any negative feedback as a buyer (I'm sure I have at some point but couldn't find/remember one).  Noticed that I've left 6725 feedbacks yet have only received 3434, basically half.....  Although I'm sure I've missed a few, I've basically left feedback for every eBay transaction I've ever had, but then again us old-timers remember when feedback was everything on this site.

Call CS, see if they'll remove the negative.

Ian