Thinking it cost more with 〜気がする

Grammar Explanation: Thinking or feeling something with 〜気がする

As thanks for Naho making him lunches, Kakeru gives her a jewel-encrusted hair clip. In her room later, Naho looks over the piece.

菜穂(なほ):: 「絶対(ぜったい)お弁当代(べんとうだい)より高(たか)い気(き)がする」; "I think it definitely cost more than lunch."