money pit

US /ˈmʌn.i pɪt/
UK /ˈmʌn.i pɪt/
"money pit" picture
1.

金食い虫, 無駄な出費

something that costs a lot of money to operate or maintain

:
That old car has become a real money pit.
あの古い車は本当に金食い虫になった。
Buying that huge house was a mistake; it's been a money pit ever since.
あの大きな家を買ったのは間違いだった。それ以来ずっと金食い虫だ。