That's correct. If you only do a partial refund, you are not charged the 30 cent fee (assuming there is more than 30 cents left after the refund). However, if you do a full refund, then you are charged the 30 cent fee. I have noticed there are a few times when I am not charged this fee even when doing the full refund, and I believe it is when I do the full refund the same day that the buyer paid for the item. (This happened a couple of times when I realized that I had already sold the item, and then mistakenly re-listed it again when it sold again.
)