"No bump system, never thought of that seems like a good concept. Update your sales ad until your heart is content, reduce pricing daily if you want - But your post won't instantly go back to the top to flood out others, as is the intention of bumps."
Not possible, sorry. As in other areas, there is a 60 minute window to modify posts. After that, the only way to adjust prices is to "Reply"
As you say, Jim, a little common sense helps.
