If you`re looking at buying an early car, say 2001-2002 they were plagued with water leaks or ingress from around the A-pillar area. Feel the carpets to see if there`s dampness especially in the front foot wells particularly. Now lots of these early cars were repaired under The Mini warranty, if it`s not been rectified, the dampness will cause no end of electrical problems and could cost up to £1000 to put right. The ECU or DME in BMW language is about £250 alone to replace. The BC1 unit that’s the body control module is located in the foot well, that will definitely be destroyed if water gets into that. So there were some modifications that were made to resolve the issue, but unless the rectification has been made there`s still a chance water has got in, so it’s important to make checks of all the electrical systems, for example the central locking & the lights. What you can do is make a call to a main dealer and quote the Vehicle Identification Number (VIN) to ask if any warranty work has been done on the Mini. If fact get a printout plus all the service history carried out at the dealership.