Just thought of some more advice that might be helpful to you.
Play the quests, like weapons quest, food quest, toy quest etc... for atleast a week or so to g et a good feel for the types of items that people who do the quests are looking for in merchant shops- example- Pepperoni pizza and Mint and strawberry milkshakes (food quest) or Jingle cage balls and gold frisbee's (Toy Quest) or Mini axe of rainbow wrath and vogar battle axes(weapon quest) Or How to hatch a Mirabilis egg and Gold stardust and the cyid (Book Quest).
Also, people are probably looking to build up their food supply again after turning everything over to find the feast, so they need lots of healthy food and Meat like various types of steak and fish ect.... also cheese cake and cream pies are probably wanted as well.