Baldeelox

Just bought a used 2006 C280 4matic. This is my first European vehicle. It has a couple issues that I'm willing to live with but, the awd was a bonus for me. I'm looking to move up from the stock 16" rims. Are the front calipers single or 2 piston? If single, what 2 piston calipers will bolt on and will I have to go with larger rotors when going to 2 piston?