Your goal here is to soften, dissolve, and wash away grease particles easily. This is why you need a pressure washer that ejects hot water or steam. The high temperatures will eventually soften the grease and let you wash it off any surface easily. Using cold water can work but only if you use high quality degreasing solutions, which are quite expensive and emits harmful fumes. It is measured in PSI. The amount of PSI you should get for a pressure washer should at least be 2000PSI. This will ensure that the force will be strong enough to loosen dirt. You should also get a pressure washer that expels water for at least 2 gallons per minute or GPL. These are the things that you should look for in a pressure washer when you are planning to clean the exterior of your house. You can use the soap attachment with a cleaning solution to get rid of grease and grime under your barbecue grill. Then, before the soap dries on the deck, wash it off with the high pressure washer. The high pressure will help remove stains and loosen or remove dirt on the patio wood deck. Just remember to spray the deck with the nozzle remaining a constant 12 to 14 inches away from the deck. With a pressure washer, you will be able to get rid of these stains as well as barnacles or any other contaminants that have attached on to your boat. You can also use pressure washers to clean the sidewalk. With this tool, you will be able to make your sidewalk look immaculately clean. Keep in mind that power washers are powerful tools. For example, you know how hard it is to remove the oil drips from your car on the garage concrete floor. With the hot water pressure washer, the heat of the water will soften the stain and the pressure will simply wash it away. And, because the water is super heated, it will be able to disinfect the surface as the heat will kill bacteria and other microscopic organisms. If you are planning on taking on a much tougher cleaning job, your best choice would be the hot water or steam pressure washer. Steam pressure washers are the most powerful type of pressure washer as it can dissolve stubborn or hard to remove deposits from almost any surface. If you can, try to get a tri-mode pressure washer.