What I would also like to see
1. The terms of service displayed when a members is viewing the ad. My terms of service are relevant to both the seller and buyer.
2. A purchase option. When a member ads an item you should have a place for their PayPal email if they have one. So now if another members wants to purchase said item they would select the purchase item option. This would take them to the PayPal page to pay for said item. The seller would then also get a PM.
With the above you would also need to list how many items are for sale. So as in our store that would be unlimited. If you have a limited number of these items once that limit is reached it should flag that item as sold. You could also have a counter indicating how many items are still available to be sold as they are sold.
Otherwise this is an awesome mod all round congratulations on it