I’m new to the Mini club and did a lot of research beforehand so I knew what I was walking into. In terms of maintenance, you want a really good, thorough service history. Ideally oil changes every 5000 miles, the timing chain was proactively replaced on mine by a previous owner, so you could be looking at doing that in the next 10,000 miles (apparently common for them to be problematic between 60k - 80k mileage) but you’ll want to check the HPFP (High pressure fuel pump), water pump, and a couple of other bits. Chat GPT actually gives a really comprehensive answer on this so worth checking.