If it's got 2.5 years remaining on the warranty, then you can take it to ANY Mini dealer for warranty work to be carried out.
No reason at all for the dealer to offer you 'their own' warranty.
The car will be covered by The Sale of Goods Act, anyway.
As long as it's been serviced according to schedule - it may have exceeded the mileage criteria.
Good point BT, make sure the service history is spot on, hopefully at 6 months old it hasn't yet been in for service, but double check mileage requirements to be sure.
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