At my former work I had to clean a 2 story building with a pressure washer. I got a extendable wand that helped, but it got pretty tiring after a few hours of use. I got it from Northern, here's a link:

Here is a link that might be useful: Pressure washer wand

Thanks for the replies! Greg, that extension wand looks interesting...sounds like most reviewers agree with you that it's hard to handle (especially at full extension), but as I said I won't be using it very often. So that may be the most economical solution for me.

I just bought the 18ft one from Northern Tool. Its a nice wand and I purchased the gutter cleaning attachment. I'm going to use it for the first time this weekend. Either way, I think you will need something a bit more powerful than the electric unit you have now. Something with at least 2500 psi should work. I bought a Ridgid 3000psi machine for 399 at home depot. It has a subaru robin engine that it the easiest engine to start and is not that loud. Also this was comes with AR brass head pump. While its not a top of the line Cat pump, its a good axial cam pump that should last a long time. I really like my pw. I noticed lowes a similiar machine with a briggs engine same psi for 389. I know HD and lowes have pw with less psi for less $$.

Be careful at HD and Lowes (or anywhere for that matter) as most of the HD and Lowes models are/were Powermate. Powermate is bankrupt and there are no parts or warranties.

Thats one of the reasons I went with the Ridgid 3000psi machine. The pw has a subaru robin engine and an AR pump, both of which I can get parts for or replace if they break.

tractorbeam, also, make sure that there's not a limit on the length of an extension wand for your unit like on my karcher washer - will never buy another, btw.