let the buyer beware

Calque of Latin caveat ēmptor.

let the buyer beware (third-person singular simple present lets the buyer beware, present participle letting the buyer beware, simple past and past participle let the buyer beware)

1. (informal, idiomatic) It is the buyer’s responsibility to ensure the soundness of goods or services prior to their purchase.
   • 1645 March 4, John Milton, “Tetrachordon, or Expoſitions upon the four chief place of Scripture which treat of Marriage, or Nullities in Marriage”, in A Complete Collection of the Hiſtorical, Political, and Miſcellaneous Works of John Milton, both Engliſh and Latin, volume 1, published 1698, page 348:

     Why ſhould his own error bind him, rather then the others fraud acquit him? Let the buyer beware, ſaith the old Law-beaten termer.