BMW Repair: oily water spewing from underside of car, upper radiator hose, coolant leak

Question
I have a BMW 2001 525i with 106,000 miles and well maintained.  I was pulling into my garage and noticed oily water coming from the underside of the car, then it started to overheat.  What do you think is wrong and what can I expect to pay for the repair?

Answer
Jeff, sounds like a coolant leak. Take the car in and have the cooling system pressure tested for leaks. Tow the car to the repair shop. I recommend flat bed tow only. It is impossible to know the condition or extent of the damage to the cooling system from across the Internet so I can't tell you how much it will cost. I would recommend replacing the thermostat and upper radiator hose as part of what ever else is diagnosed at they do not seal well or operate correctly once overheated with any age to them. Use BMW coolant if possible.
-Evan