i dont know.
i dont play the game that far...i think.
and you dont need to buy in Materials Shop.
you can just hack the Items, you already had.
the only thing is you need to have enough space in your storage building.
if your Storehouse(Items) had max capacity of 10
editing amount any item to 500 will not save it as it pass the max limit.
so you need to hack Storehouse max limit.
and to be honest, you dont want to do that as it can break the game the more you hack the items.
to a point where the game just freeze or crash whenever you open it.
even so it not freeze or crash, the game will be so lagging(1-2fps),it become so unplayable.