G'Day
I've had a K'Archer for three years now, bought it for washing down a weatherboard house which was great, now with the water restrictions it gets used frequently to wash the cars.
I used at the weekend it to clean out the garage at the rental I'm working on - really efficient as it pushes the water out of the area more effectively than just having a hose on full blast.
For that reason it's also good for washing windows - the pressurised jet reaches further without thudding on the windows.
I have found the couple of hundred dollars well spent. Check around for prices, Bunnings are a good benchmark and compare from there.
My model is one-up-from-basic. It also has a little feeder hose which can be put into a bucket of soapy water and a low pressure nozzle if you are wanting to clean without blasting.
Cheers
Kristine