Removing a thread on the For sale Forum

[Wpns 421]

I have posted and sold a few things on the For Sale forum and wish to remove my ad but cannot. Is there some way that the moderators could put a time limit on the ads say 1-3 months and then it would disappear. It's a bit of a nuisance when you see something interesting and then find out the ad is 2 years old or the item was sold a long time ago.. Suggestion Gilles