I have added a plugin that lets you use chests instead of signs. You can still use the old trade signs if you want, and I also added a plugin to improve those by adding back item-ids. (If you need help creating trade signs, try this)
So anyways, for the new chest-based shops, all you have to do is place a chest, and hit (left-click) the chest with the item you want to sell. Then it will ask you to type the price in chat; Simply type a number and send it.
If successful, it should have automatically added a sign to the chest with all the info. You can left-click that sign to see info about it, or right-click on the sign to edit it, such as changing the price. To fill up the shop, you simply place the items in the chest, and the amount on the sign will be automatically updated with the items in stock. The money from sales will be automatically sent to you.
To buy from a shop, hit the sign and it will ask how many you want to buy. Easy.
Advanced
Use the command “/qs staff add <player>” to let someone else manage your shop as a shop staff member. Other relevant commands are “/qs staff del <player>” to remove a person from staff, “/qs staff clear” to remove all staff, and “/qs staff list” to see a list of all the staff for your shop.
“/qs find <item-partial-name>” will show the closest shop that sells an item you specify within a 100 block search distance.
You can also create “free” chests, if you want to just dump in stuff to give away for free.
In other news:
There is now 1 player shop in EpicTown so far! Check it out near the warp point.