Originally Posted by whisper
I have always used Karcher.
Quality products. Even if it means increasing your budget some-what, get something that produces at least 140 bar. Second-hand is fine, but check the auto-start stop works (with water flow on), it doesn't leak and it achieves operating pressure. Petrol ones are usually higher pressure, usually hot water steam units, and most will have had a hard life in commercial sector washing lorries dawn till dusk!
Regards shifting grime, a small deck scrubber and mild detergent works wonders, then use the Karcher.