Anyone who has sold items via their city's Trade Depot will notice after a period of time a number of bugs and inefficiencies that can reduce your trading value from thousands of Simoleans per day all the way down to zero.
Here are the 6 most effective ways I have found to deal with this:
1) Not Completely Filling all Your Trade Slots:
Always leave a 1 or 2 slots open when you stock up your Trade Depot so that incase of the Global Trade HQ having a bad hair day or just lack of demand for whatever reasons you can still come back a few hours later to add additional items which also brings renewed attention to your old stock,
2) Advertising:
Every 5 minutes you get a free Advertising Spot in the Global Trade HQ for you to use - quite often if you advertise a popular item like Expansion or Storage material at a reasonable price you will find that most of your other stock has sold out as well. The best way of using the free advertising is to upload all the items you intend to first and then start with the first advertising spot on a competitively priced piece in order to attract larger numbers of potential buyers and you may only have to advertise 2, 3 or 4 times before your entire load gets sold.
