I did it! I think I also could do it before the map was nerfed, but I wanted to save my golds!
An odd thing was that I got PURIST badge,
but I used the GG->
I used preps.
There is a bug which same items are duplicated.
Maybe this bug can be existed in all triple quests.
EX)
1. STAGE1: Buy a Spoon in the st1 shop.
2. STAGE2: the Spoon is dropped at starting point, because your inventory is fulled.
3. STAGE2: Another Spoon is in the shop.
EDIT: Grammar Check