Yes, nightingale made me think of a building of an alchemist laboratory. There you can add recipies that you buy in shop or discover in explore. The recipies could cost in gold or silver, depeneding on the item it creates. When at the alchemist lab, a drop down box you select what you want to create. When an item is selected it goes to a new page with the standard materials needed, pet needed, normal item creation page. There it can be created if proper materials have been gathered. All of this should be difficult enough to not mess up the prices of such items, but not so hard that no one tries to create something.
Edit: It could be a high level of the normal laboratory?
Has I done good with contributing to idea?