To complete your Animal Crossing Wild World catalog you do not actually need to purchase the item from Tom Nook. This means that you can get many items into your catalog by simply picking them up and adding them to your inventory for a moment.
One way to do this is to visit other towns and borrow items for a brief moment from your friends. In exchange you can let them visit your town and borrow items that you own but that they are missing from their catalogue. This can allow you to order items from Tom Nook back in your own town without causing any real inconvenience to your friends.
This is one Animal Crossing Wild World hint that I truly do recommend using because it reflects the intention of the game play and encourages player interaction. Unlike many cheats it does not try to break the game or make it less fun to play.
Visit the summary of Animal Crossing Wild World Cheats and Hints.
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