I don't know how much it costs until I know the weight.
ーI can't give you a price until I weigh it.
「重さを量るまで金額を出せません」
to give a price で「値段を言う・出す」
to weigh で「量る・はかりにかける」
ーI don't know how much it costs until I know the weight.
「重さを出すまで値段が分かりません」
to cost で「(金額が）かかる・（値段が）する」
weight で「重さ・重量」
ご参考まで！
カナダ 
