Board Thread:General Discussion/@comment-35315474-20180507180309/@comment-35319541-20180509060347

Not to try to make collections that take dragonflies and cotton-they are way too expensive, and there are much lower collections that maybe offer three of the item you need for far less cost for the fixers. I finally took the plunge and made dragonflies and cotton just to get some of the ungiftables off the board (so to speak and ate thru 150,000 coins, and it took time to do so.

And if you don't mind a lower treasure chest count banishing monsters, stick to the ones that don't eat your coins.