Can you voluntarily relinquish the goods without penalty in spaces 20 through 25 to raise the price if you should wish to do so?
From the waterframe rulebook page 24 :
The player may not use spaces with goods as price
spaces. In the rare case that the player already has
placed the price indicator on one of his last spaces, he
may only store as many goods of this kind as there are
unoccupied spaces to the right of the price
The player may store a maximum of five
goods of any kind. If he has to place
additional goods, he always may
return goods from the warehouse to
the common supply (without receiving
any compensation!) to make
room for other goods. He may also
transfer goods to the large warehouse if
there is room.
The rulebook mention that you can return goods to make place for other. I doesn't mention if you can return goods when setting the price. I would allow it.
Stefan would probably correct me if I'm wrong.