a pig in a poke

"A pig in a poke" is a phrase used to refer to a purchase made without prior inspection or investigation, typically involving a product or deal that appears valuable or desirable but may turn out to be of poor quality or have hidden flaws. It originated from the practice of dishonest sellers in medieval times who would deceive buyers by putting a less valuable animal, like a cat, inside a bag (poke) instead of the promised pig. Therefore, it serves as a warning against making decisions or purchases without careful consideration.