Never mind, just found this:
Q: Can I post a thread for EACH item I want to sell?
A: Sure, but please only keep ONE active thread open. Do NOT have multiple threads open simultaneously, you can just as easily sell 10 items in one thread instead of selling one item separately in 10 different threads. This helps us keep the FS/T section less cluttered, and prevents peoples threads from getting "bumped" too far down.
So mods, please combine all the for sale threads open simultaneously by the same seller. Often times I see half of the threads in this sub-forum are from one seller, posted minutes apart. Thanks.