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]
(..) Right, which is probably why you're driving around in those junky cars. No, we bought those junk boxes because driving around in nice cars got too expensive. I cannot tell you how many times some feminazi shattered their windshields or keyed their cars. Forensic evidence shows (..)2016 TvShow: Bones Title: The Murder of the Meninist Season: 11 Episode 12