Windows 10 keys
Windows 10 keys
I checked online and found that buying Windows 10 Pro OEM keys on eBay is often affordable. Many reviews are positive, and some users share that they obtained the software for a low price without issues. It seems reasonable to consider purchasing one if you need it.
I've bought keys from eBay and keystores before. I haven't faced any issues, but it's wise to pay with PayPal for protection against chargebacks.
The cheap keys often have some issues. They usually function but might be obtained illegally or aren't meant for resale (like MSDN keys). Remember, eBay buyer protection doesn't cover digital downloads or key sales, so a bad key could leave you without recourse. However, I did purchase a Steam key from eBay before and received my money back within hours, showing they do offer some protection. It's best to keep all communication with the seller via eBay messages, so if you need a refund, they can review everything.
I've confirmed the details in the guidelines for each platform and for MS OEMs. You can verify them online. I've already purchased the full OEM price for my copy from 2010, and I suggest you do the same. Alternatively, buying the retail key would cost about $50 more.