The function, idea, or action comes first, so start with "pipi'i" for expensive/high. It will read as "High the price..."
"Kēia" comes before the object, not after: "kēia pa'a kāma'a." - "...this pair (of) shoes."
So, what is the special rule for this prompt? I tried "o pa'a kāma'a kēia" and was marked wrong.