As said above, get a Karcher one.

I've seen one for about £80, and it has a small hose attached so that you can "sea foam" the car. It's also great to blast grime off the patio and walls.

Never heard of jet washers "making shit of" paintwork though. I can only think your referring to the ones at tesco and whatnot, as people don't realise there is always a load of grit in the brushes and there rubbing it into there paintwork!