You can start earning from signature campaigns, if you have higher rank accounts then that will be added advantage for you and you need to join campaign with higher pay outs.
I think he wants to earn the amount asked now and not wait 5-7 months to reach that level in membership to earn that amount from signature campaigning.
I don't believe buying an account for that sole purpose is recommended either because the one's in charge of those higher paying campaigns look at past post quality and most accounts being sold are of poor post quality such as one liners and spam posts.
In my opinion, if there was someone who was to spam out poor messages initially to level their account and then turned around and started making decent posts with actual content, I think I would allow for them to join a campaign. As long as they don't start spamming again once they join, I'd definitely allow for them to participate.