A dictionary of Proverbs (Oxford Paperback Reference)

buy see also why buy a COW when milk is so cheap?; MONEY can’t buy happiness; one WHITE foot, buy him.
Let the BUYER beware
A warning that the buyer must satisfy himself of the nature and value of a purchase before proceeding with the transaction. The Latin tag caveat emptor is also frequently found: caveat emptor, quia ignorare non debuit quod jus alienum emit, let the purchaser beware, for he ought not to be ignorant of the nature of the property which he is buying from another party. See also the next proverb.

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  1523 J. FITZHERBERT Husbandry 36 And [if] he [a horse] be tame and haue ben rydden vpon than caveat emptor be ware thou byer. 1592 NASHE Pierce Penniless I. 155 Sed caueat emptor, Let the interpreter beware. 1607 E. SHARPHAM Fleire II. C4 They are no prouerb breakers: beware the buyer say they. 1927 Times 29 Sept. 10 We dislike very much, whether it is put in Latin or in English, the phrase ‘Let the buyer beware!’ 1974 D. FRANCIS Knock Down xi. ’Caveat emptor,’ I said. ‘What does that mean?’ ‘Buyer beware.’ ‘I know one buyer who’ll beware for the rest of his life.’ 2001 Washington Times 24 Sept. All It’s caveat emptor as charities and others appeal for relief donations in the wake of the Sept. 11 terrorist attacks. Only this time ‘let the buyer beware’ should probably read ‘let the donor beware.’ "buying and selling; caution
  

The BUYER has need of a hundred eyes, the seller of but one
Cf. It. chi compra ha bisogna di cent’ occhi; chi vende n’ha assai di uno, he who buys needs a hundred eyes; he who sells but one.

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  1640 G. HERBERT Outlandish Proverbs no. 390 The buyer needes a hundred eyes, the seller not one. 1745 B. FRANKLIN Poor Richard’s Almanack (July) He who buys had need have 100 Eyes, but one’s enough for him that sells the Stuff. 1800 M. EDGEWORTH Parent’s Assistant (ed. 3) III. 86 He taught him.. to get.. from customers by taking advantage of their ignorance. .. He often repeated.. ‘The buyer has need of a hundred eyes, the seller of but one.’ 1928 Illustrated Sporting & Dramatic News 7 Jan. 27 (caption) The buyer has need of a hundred eyes. The seller of but one. "buying and selling; caution