Question Please help with Windows 10 activation through COA licenses

[Techxz]

I currently have a PC with a copy of Windows 10 that has not been activated. I want to activate it, so I can sell the PC with a genuine Windows 10 license online.

From my understanding, what computer refurbishers do on websites like eBay is that they activate windows through a Windows COA license.

I have also found several eBay sellers that are selling Windows 10 OEM COA stickers. Are those stickers what I am looking for or do I need a retail COA sticker assuming a retail COA sticker is even a thing?

What is a Microsoft and eBay compliant way of legally activating this copy of Windows before I sell it on eBay?

 

[bignastyid]

Buy a license, OEM or Retail A proper win 10 license is going to cost around $100. Be weary of any options vastly cheaper as you could end up with a bad key.