costing an arm and a leg vs overmuch

costing an arm and a leg

overmuch

det

  • Very much; too much 

adj

  • Excessive. 

noun

  • An excessive amount; too much. 

adv

  • Too much; overly much 

How often have the words costing an arm and a leg and overmuch occurred in a corpus of books? (source: Google Ngram Viewer )