That's highway robbery.
 →   순날강도군.(값이 너무비싸다)

[예문]
A :How much did you pay for this traditional Korean doll?
  이 한국전통인형 얼마줬어?

B:$300 including local tax.
 세금포함해서 300달러줬어.

A:What!!!! That's highway robbery! You can buy the same thing eleswhere for only $30!
  뭐라구! 너바가지썼어.똑같은거 30달러면 살수있는데.

 * highway robbery : 백주강도,노상강도,폭리.