The third party who makes a straw purchase for another person.

One who makes a living traveling to ranches and buying cattle on behalf of meatpackers.

A person who panic-buys.

Used as a warning to a potential buyer of a product about its defects. / (figuratively, by extension, often humorous) Exhortation for the listener to exercise caution.

plural of first-time buyer

A person purchasing a house for the first time, as opposed to one who already owns a house and is selling it in order to buy another. / A person who purchases something for the first time.

It is the buyer’s responsibility to ensure the soundness of goods or services prior to his purchase of them.