›more expensive than is reasonable: extortionate fee/price/rate, etc.Most retailers charge extortionate prices for extended warranties - often more than three times as much as an independent provider.
extortionately/ɪkˈstɔːʃənətli//-ˈstɔːr-/adverb›The government has agreed on measures that protect the renewable energy industry from extortionately high national grid access charges.