Her decision to leave the company proved to be an 'expensive' mistake. [=a mistake that caused her to lose a lot of money]
They live in an 'expensive' neighborhood. [=a neighborhood in which houses, apartments, etc., cost a lot to buy or rent]
an 'expensive' shop [=a shop that sells expensive things]
(..) .. How Iong have we waited? .. , wasn't it, oId bean? .. The most expensive cup of tea in history. .. Manhattan, for a handfuI of beads. .. How. .. (..)1999 Wild Wild West