I am reading the Japanese translation of Matilda by Roald Dahl. Spoilers ahead.
Mr. Wormwood has just finished explaining how he cheats his customers at his second hand car store. He fills the engine with hay to get rubbish cars to work again!
Matilda (his daughter) then asks him:
to which he replies:
I interpreted 買ったやつ to mean "the guy who bought the car". Mr. Wormwood is rather impolite and would have no problem referring to his customers as such.
However, others have cast doubt on this interpretation. An opportunity to learn presents itself! Which is more likely to be correct here?
After this debacle I looked up the original English, here it is:
"How long will it run like that before it starts rattling again?" [Matilda asked him.]
"Long enough for the buyer to get a good distance away,"