Dragon Market costs 1,000 and yields 1,000 upon the completion of its construction, and has a size of 4x4.
This building allows you to select either or to be produced and collected in 12 hours, whether or not your friends accept your request for assistance.
Each assist from your neighbours will increase the resource collected depending on several variables, including your game level.
The Post-LaW update to Dragon Market appears to have removed the cap for resource collection from it. If you have many active neighbours, you may find it worthwhile to collect resources from it on PC.
Starting 28/5/2014, you can collect from the Dragon Market every 6 hours instead of every 12.
Before you start, you must know about the base amount of food or gold you will get. There is a bonus in production when at least one of your friends accepts your request, and a further bonus when 10 friends accept your request.