cost an arm and a leg

Meaning: すごくお金のかかる、目が飛び出るほど高価な

For Example:

‣ I bumped my car into the wall of the garage last week, and it costed an arm and a leg to fix it.

車庫の壁に先週車ぶつけてしもて、修理するんにがいにいったわ。

‣ You should buy that dress. It looks perfect on you and it doesn't cost you an arm and a leg.

あのドレス買うべきや。すごく似合てたし、そんなに目が飛び出るほど高いわけでもない やん。

Synonym:

very expensive, very costly