I wonder if such areas should have a type of permanence, like the auction threads? Or would that be overkill?
i personally think all selling areas should not let someone change something without a history of what was changed.
Well locking all posts like the auction threads would be a good start, if the OP needs to correct something they can update with a new post in that thread.
A better solution would be to create a section that could be appended to the original post so all the thread goers can see it, but also see it is in addition to the original post.
Example:
I am selling a fox for 2,000 btc.
And then an amendment to the original post:
(The important part being they cannot modify the original post at all, only append.)
I am selling a fox for 2,000 btc.
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Update to Post #1:
Sorry its not a fox, but rather a goldfish.
I wonder if that could work because it would allow all newcomers to be up to date from post 1 instead of having to read the entire thing.