oil, grease, coolant leak???

Just got a used 2009 mini cooper.  the check engine light came on, went to dealership (not mini)  they said it was something to do with the gas cap.  next week, driving down the highway, steam/smoke starts billowing out (no ck eng light) pull off to the side, black fluid was pouring out and smoking/steaming.  towed to service.  they start out telling me it wasnt oil, it was "black coolant".  next they tell me it was a combination of coolant and "grease" which sprayed around and mixed together on its way out of the car because of failure of the water pump.  one week later, they say it has nothing to do with the water pump, it was some "plastic connector" which attaches to the water pump and this caused a loss of fluid and "grease" which sprayed around.  obviously they   have no idea what is going on and i am not trusting them AT ALL at this point!!  this is all happening during my 30 day warranty (good thing), but now they have had the car for a week and a half of those 30 days!!  Does anything they are saying make sense??