1800 PSI should do a good job on household cleaning- please make sure the unit is getting enough water by using a 5/8" garden hose no longer than 50-75 feet long connected to city water.
Any detergent you use needs to be labeled as "pressure washer safe" since it will be drawn through your pump with the stream of water. It needs to be thin enough for the water to pick it up- watery is good; thick like dish detergent won't work.
Wood and cement respond to different cleaners. I like the
Simple Green Deck & Fence Cleaner since the 1 gallon jug makes 11 gallons of detergent when it's properly diluted. Be careful cleaning wood with your Turbo nozzle- the spray is intense enough it can mark the wood.
Even though it's biodegradable, give all your landscaping a good drink of clean water before you use the detergent; it will help keep your leaves from browning.
For concrete I like Simple Green Concrete Cleaner, not only because you get a lot of detergent for the money once it's diluted, but also because it works well. Pre-treat stains and oil with the detergent and let it sit for a bit so the detergent can bring the stain to the surface; then use your turbo nozzle to blast the stain away.
You might like the results from Karcher's T300 Surface Cleaner on concrete- it leaves a smoother finish than you can get with your regular spray nozzle.
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