Multiply items:
Enter a town, locate a training room, and saved the game. Create a
temporary character. Remove (not delete), one of your regular
characters from the party. Add the temporary character to the party.
Place the item or weapon to be duplicated into the temporary
character's inventory. Remove the temporary character from the party.
Add the regular character back into the party. Remove all characters
from the party, then reload the saved game. The item or weapon should
be in both the original and temporary characters' inventories. Repeat
this process to duplicate the item or weapon as many times as needed.

Quick gold:
Create one permanent and six temporary characters. Add all six
characters to a party and transfer all gold to the permanent
character's inventory. Have the permanent character buy any equipment
or items. Remove the permanent character from the party. Create and
add another permanent character to the party and repeat this process
until all permanent characters have the desired gold, items, or
weapons.