Membership plugin recommendation please

Could anyone recommend a free or paid WP plugin that would allow me to charge users (authors) time-based subscriptions to their own posts? I know it sounds counter intuitive, but site users (authors) are able to add a post and I need to make that post free for 14 days and then be able to charge for being able to further visit that post. When the subscription runs out, the content should be hidden and an option to prolong the subscription should show up. Any ideas are appreciated.