Like everything Dave, you get what you pay for. Here's my twopenneth.....
And a few hopefully helpful hints.
Agree entirely on the use of pressure washers on cars. They are an immensively useful tool but NEVER ever use high pressure on a car, especially the paint unless you want to start stripping it for a respray. Ok for low/medium to rinse off etc though. Pull the trigger away from the car before you start using it - that's every time you pick it up. Otherwise you'll accidentally blast the car at some point.
I have a Kaercher (admittedly not a cheap one) but, it does 150bar. That's 50% more powerful than most. It gets used at that pressure only on the patio and the conservatory every spring. It makes what used to be an all day marathon into a two hour job.
The advantages of Kaercher are the tools.
From patio cleaner, brushes, extensions etc. Makes them versatile.
The standard hose on cheaper units is however generally short. Doing a large car can be pain because they don't stretch all around without having to move the washer itself.
A 8 metre or 10m hose is much better. They are a bit difficult to control as they constantly want to curl up. Have a reel that keeps it tidy though.
I also use a snow foam attachment. Much better and quicker than a hose based one. 15 seconds to cover the whole car. Much quicker and even coverage.
OK - It uses more foam stuff but not dramatically more if your careful. Well worth it.
I also have a wheel brush but I rarely use it on the washer. Just as easy to use a bucket with that to be honest.
For use on the conservatory roof (and upstairs Windows that can't easily be reached) I use a 3m extension with variable angle/power nozzle. That also does under the cars to remove winter salt etc. Great addition.
They MUST be stored where frost can't get them. If water freezes in the pump you have a dead washer.
