I researched and read reviews, and Elite Power Washing came up on top.  Both my neighbor and myself hired them to power wash our houses and sidewalks.  They did an excellent job.  They also ended up cleaning out our gutters on both our houses.  Now all of our neighbors comment on how good our two houses look, almost like they were just painted.  There were areas I was going to paint but this worked so well those areas now look freshly painted and I'm not going to have to do anything.  They were also very kind, I saw an area that they had missed on my neighbor's chimney after they had rolled up and stored everything into their truck, and it was no problem.  They unpacked all of their equipment, hooked it all up again and spent another 45 minutes making it right.  We've had two neighbors approach us to get their contact information because our houses look so good now and they also want to hire them for their houses.  I highly recommend them.