As we grow, this will tend to happen, but as these are discovered could they be deleted and and a thread created which tells what deal has been deleted and why. that way the poster knows what happened.
Eg - Thread title - What happened to my post?
Original Topic heading - then Poster - link to other deal
Big Bill Payoff - Freddie Smith
Duplicate - see xxxx
or Spam
or inappropriate
etc
I posted a double on a Dominos voucher which one other member voted negative and explained that it was a double post. In this case I deleted it myself, but not sure if others know or are willing to do that themselves
I would/do that all the time if I post a duplicate - I deleted 2 duplicates last week.