Step #1 The lady in the bank you need to talk to her and the armor shop guy at the same time. The trick to doing this is once you talk to her she will take one step forward before she turns and walks away so you have to talk to her many times. every time she takes a step talk to her and guide her to the shop.

Step #2 It should look like this now press A until the lady stops talking. Once she's done talking you will be able to walk around but cant see where your going which takes you to step #3

Step #3 Move slightly to the left and press A remember you cant see where your walking (doesn't matter what other shop you go to for this step) It should look like this then Press B then A.

Step #4 Now you should have the shop window open and can run around like this.

Step #5 With the screen Exactly like above go to your Check Room (BANK) and choose Take then Item Press A once more you should see a YES or NO don't pick Either when you get there Press B, B, then A.

Step #6 Now you can walk around with the check room (Bank) menu up press start. Highlight Item Pack and take at same time press A, Then Items and Items and press A. Now take what you want duped from the check room once you took what you want duped press B and Highlight Items and Deposit Press A.

Highlight what you took from check room and Item press A find item your duping in top window now and highlight it and DROP And Press A twice Now you have one on the ground and one in the Check room

Congratulations You just Duped your 1st Item now good luck!

I deposited the Item to show there is 2 now