All Cherished MINIs come with a 30 Day/1,000 Miles exchange/refund guarantee...
MINI Promise
We've total confidence in every Cherished MINI. So much so, that if anything goes wrong in the first 30 days or 1,000 miles of your ownership (whichever is sooner) and we can't sort it out, you can exchange it or, if we can't arrange an appropriate exchange, we'll give you a refund. This does not affect your statutory rights.
...but other than that buyers of used cars are covered by the same legal rights as those of new cars.