I bought an electric one at an auction about two years back for $8.
It looks like a box on wheels.. about 4 feet high, and about 16" wide and deep.
The way it works is you can fill it up with water and soap, or just water, or hook up a garden hose and have the fresh garden hose supply mixed with whatever is in the tank.
I don't know what the GPM or PSI on the thing is.. but it works great, and no gas to buy.
Of course there is the portability issue, but let's face it.. you still pretty much have to have a garden hose hooked up to the thing, and just about anywhere you can stretch a garden hose to, you can get an extension cord to.. so no big deal.
My mother in law has a gas powered pressure washer she bought from Home Depot a year ago.. it seemed like a pain in the *** and weighed 4 times as much, and seemed like you could spray for about 5 minutes, then have to wait for it to build pressure back up.
But i'm sure she just bought some cheapo deal.. for something with a gas powered engine slapped on it, I was quite unimpressed.
