The garage I work for sell these like hotcakes they are very popular. Good looking car. However in my experience:
They are generally a higher price than other cars in the same vein as they are a BMW and sought after. They all suffer from noisy steering pumps its part of owning one. They also nearly all need some of the steering column componants replaced (usually warranty, make sure its been done). They cannot fit tallish adults comfortably in the rear and the boot is small.
Ignore the Mini one model and go for a Cooper. A/C is a must it hits resell values if not fitted. Also wacky colours/stickers might be fun now, but resell might be harder as you have to find someone with the same taste.
Look for cars with "TLC pack" it gives you free serviceing.
If you can wait a bit a facelifted version is out soon and that will cause more older cars to become available as people upgrade.