The price for 0days is highly variable according to this presentation (starting slide 65): https://github.com/mdowd79/presentations/blob/main/bluehat2023-mdowd

The price for 0days is highly variable according to this presentation (starting slide 65): https://github.com/mdowd79/presentations/blob/main/bluehat2023-mdowd-final.pdf https://github.com/mdowd79/presentations/blob/main/bluehat20... The same presentation also mentions (starting slide 17) how the requirements of 0days differs from public research, which is why some vulnerabilities would be difficult to sell.