Hey there, just to add to what everyone else is saying:
If you're buying privately, I'd made sure you were absolutely certain that the gearbox is ok. I needed mine replacing at about 32,000 miles because it just fell to bits - this is a widely recognized problem. That's
expensive if not covered by a cherished warranty!
And keep an eye on the power steering, in first generation MINIs it seems a common problem is for the power steering pump to fail. I'm having mine repaired today - out of warranty, but MINI is helping with the cost as a goodwill gesture.
And finally, I do hope you find a fantastic MINI - and welcome to MINI2.com!
All the best,
Andrew.