I purchased an 07 mini cooper s a few weeks ago and like every new car there are always a few odds and ends to take care of. First there is a small coolant leak i have traced back to the water temp housing. It may be the sensor but i haven't dug into it quite yet. Second is it has an alta exhaust and i think that the resonator is shot because once it warms up after 5 mins of driving, it begins to make a rattling noise between 2k-3k rpm. When it is hot outside and the car sits in sunlight, the sunroof wont open without assistance. Last the rear hatch wont shut sometimes after I press the release button on the key fob. If people could post solutions with what is the bet rout to tackle these problems, be my guest. I do alot of my own work myself and dont mind getting my hands dirty.

 

Seek professional help.

 

For the sunroof: do a search on here. You'll find that this is a common problem for R56. While there isn't a permanent solution, there is a service bulletin that recommends cleaning and greasing the moving parts and checking the alignment of the glass.

My own solution: In my car, gently supporting the back of the front section of glass is enough to get it to open even on the hottest days.

 

Fellow New mini owner, also didn't know all the quirks but got a decent extended warranty to help.
Sun roof needs lubricating, Google it, there are pictures posted with instructions. I bought lithium lube, but haven't gotten to it yet. It only sticks when it's really warm outside.
Coolant leak is usually the thermostat housing. It's plastic and prone to cracking, unfortunately the thermostat and housing come as one piece from mini.
My hatch also doesn't always close properly. I haven't had time to research it yet. Currently I'm waiting on mechanic to check timing chain. Goes in on Tuesday.

I'd you have a rattle, that is a good place to start, common problem on these cars especially the turbo because of poor design and maintenance