Go to the inn then save your game then go to the guild then link with your friends then go to the versus mode. Select gold. The one will risk all of his/her money then lose the battle when the winner accepts the money the loser will restart the game(just save before you battle the winner). Now, open the game and you will see your money is still there. And there you have it instant money. do this everytime you want it BUT you need a friend to link with.