expression, ichidan verb
take advantage of someone's weakness; size up a customer to overcharge
Idiomatic expression meaning to exploit someone's vulnerable position, especially in business. Originally from palanquin bearers assessing a traveler's fatigue to raise the fare.
彼はこちらの急いでいるのを見て、足元を見て高い料金をふっかけてきた。
Seeing that I was in a hurry, he took advantage of me and charged an exorbitant fee.
When I was in a weak position, they took advantage of me and made me sign an unfavorable contract.