Kacher are very good, We have had two now at this stage and are great. Wet the car with them, Wash all the heavy dirt off from around the sill's of the car etc and then bucket of warm water and a sponge for the rest of the car and then rince with the Karcher again. Best way and the smallest amount of damage to a cars paint work. Depends on how much you love your car but a full polish once every six weeks or so would help aswell.