Costco carries a couple of sturdy Arcan pressure washers as well as Karcher pressure washers. These are heavy built machines which would be great if you need to wash a big surface - as they are all quite powerful. Dirt, mud, grit etc... can over time penetrate a surface which makes it difficult to get clean without a lot of elbow grease. If you want an easier solution, then using a pressure washer would definitely be a good thing to look into. Simply with the push of a button you can get a powerful stream of water that will get any ingrained dirt off without any issues. This method is definitely to prefer if you're looking to clean the facade of a house, a driveway, pathway, a boat or any other surface that is dirty and needs cleaning. These pressure washers are gas powered, however you could probably find a fuel powered pressure washer if that would suit you better.
You can find Honda engine pressure washers, LCT MaXX engine pressure washers as well as high PSI gas powered pressure washers in various sizes. These Costco pressure washers are very durable and relatively comfortable to use. That is certainly pretty important: if you're looking to clean a rather large area such as the facade of a house, then you can't have it be uncomfortable to use. So no matter what your gardening needs are, Costco would be worth a look. They carry a surprising amount of reasonably priced home improvement things and gardening supplies which of course differ depending on the selection of size of that particular store. However as with all things at Costco, if you see something that would suit you, you better pick it ut right away because you never know if they will have that particular thing next time you come again.
Karcher 3000 PSI Gas Powered Pressure Washer
"The G 3050 OH is a compact powerhouse generating 3000 PSI, more than 60 times as much pressure as a typical garden hose. Featuring an uncluttered design with easy access to the engine and pump, this unit offers unrivaled ease of use."
Karcher 2600 PSI Gas Powered Pressure Washer
"The G 2600 PH is also equipped with a reliable, easy to start 161cc Honda GCV 160 engine and a set of four patented Pro-Style nozzles. A full line of accessories is available to further enhance the capabilities of this exciting new pressure washer. The G 2600 PH represents great value, offering German engineering at an affordable price."
Arcan 2400 PSI Gas Powered Pressure Washer
"The Arcan 2400 PSI Pressure Washer is perfect for high pressure cleaning as it is powered by an LCT MaXX series engine.The Arcan AR2400 series pressure washer is ideal for virtually all automotive, atv, motorcycle, marine, household cleaning jobs or anywhere heavy duty cleaning is needed. With EPA/CARB approval and a patented design the Arcan AR2400 series pressure washer is the on-the-spot cleaning solution."
These pressure washers can be found at costco.com