What to look for at 148 miles on a E320 2000 Benz sedan?

At 148k miles give the car a good 20-30 minute test drive. Make sure the car is cold when you start. Pay attention to chassis vibrations , possible motor/trans mounts. Make sure transmission shifting is smooth and engine has power. Listen for clunks or knocking noises over bumps , possible suspension issues . Under the hood look for signs of fluid leaks , like at valve covers or power steering pump. Check all lights , wipers , horn and all Windows and sunroof. Check heating and cooling of climate control. Make sure instrument cluster works . Basically a 2000 e320 is a very solid well made car. Ask to see any service repair papers or proof the car has been serviced regularly .