Time limits on lines?

I would like to setup a phone in the lobby that will allow free 15 minute calls, but the same number can only be called once a day and I would want it to use the same trunk all the time. Probably stored in a blacklist db and then set a cron to clear that.

This is not so much a freepbx feature but something one would have to code manually.

Just wondering if anyone had set this up already.

Thank you