I strongly advise against buying or selling old Twitter accounts, as it goes against Twitter's terms of service. Acquiring or selling accounts is considered a violation of Twitter's policies and can lead to serious consequences, such as account suspension or even legal action.
It's important to use social media platforms like Twitter ethically and responsibly. If you are looking to grow your presence on Twitter, I recommend focusing on creating engaging content, interacting with your followers, and using legitimate strategies to increase your following.