Money! Money! Money!
A tip to get rich quick is to take the blast mask or bombs and go to the bombers hideout. Quickly turn left and swim down. Avoid the big skulltula and find a ladge on the left. Bomb the cracked wall and there is a chest with 100 rupees in it. Now deposit these in the bank and reset time. Also resetting the chest. Now do this as many times as you want but it quickly gets boring. Trust me.
Hope this helps.
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