BMW M5 F10- Extended Warranty

[greido]

I'm looking to purchase an M5 F10 and having heard some horror stories about repair bills I'd like to get a car still under BMW Warranty.
I plan to go for a car less than 3 years old with less than 30,000 miles, does anyone know what the cost of an extended warranty would be once it reaches 3 years old?
Alternatively, if I bought a car that was just over 3 years old (early 2013) but with full BMW Service History, would I be able to purchase a warranty from BMW?

Thanks in advance.