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So I just finished my first cedar shake roof cleaning job and it seems to have turned out well so I thought I would post my experience here. I did a lot of research prior to the job and honestly did not find much helpful info. Obviously people do not want to share hard earned knowledge I respect that. I hope my experience can be helpful to someone and I Would love comments, advice, etc... from some of you masters out there who are established.
About me: Pressure washing for 10 years, cleaning gutters and air blowing roofs for 10 years.
The job: A long time client asked if I could remove the algae and moss from his cedar roof so I gave it a go. The roof is a 10/12 pitch, back side has a 35' drop. Two safety anchors to tie into, I was tied in at all times using a climbing harness, and prussik cords to ascend and repell. Korkers madatory. I used a  Dewalt PW 3800 psi, 4gpm. The pressure was dialed down to about 80% most of the time and I used a 45 degree fan tip. I used oxyclean (oxygen bleach) and TSP to soak the roof first, as I have read that bleach (sodium hypochlorite) damages wood. I guess the chemicals helped some but to be honest it was not that noticeable as I pressure washed parts of the roof without the chemicals for comparison and the amount of work was about the same. I think my concentration was too low, I do not have a good pump set up so I used the inline feed in my pressure washer which is down-stream of the pump, and I think my solution went on too diluted. I was careful to keep my tip a safe distance from the wood and just close enough to remove the algae. I did not notice any wood fiber being removed even at the full 3800 psi. With full pressure going with the grain seemed to work the best. With lower pressure going against the grain worked better as it leaves less marks on the wood. The problem I noticed with using full pressure going against the grain (or moving sideways to the shakes) is that it could potentially spit the shakes. So I pretty much went with the grain the whole time. Also I figured out early on that you clean one shake at a time. Obviously never spray up the roof, thats a no brainer, shakes can be dislodged and water will be driven under the shakes. I also made an effort to direct all of my strokes down the roof, and lift up before going back up the shingle as I could see water being driven up under the above shake if my tip was close to the roof on the up stroke.
The roof looked awesome, definitely brought back that nice wood color.
To seal the roof I used Chevron Shingle oil with a pump sprayer. Gave the roof a wet look.
I immediately got a request from the next door neighbor, and his turned out great as well. Meanwhile two more requests from residents on the same street. Gotta love that!
The first job was 4 thousand sq ft. It took me 4 full days just to clean and a 5th to treat.
I wore my Danner Goretex boots, and they did not stay dry, any recommendations on good boots for roofs that will stay dry?
Also any recommendations on Pressure washers? Does high volume (say 10gpm+ ) make the job easier? faster?
Any preferences on treatments, anybody ever use TWP?

I got hosed on the price. I honestly thought I was going to do this job in one day. Thats okay though I have happy clients and the jobs turned out well.
Any advice on what to charge for this type of work?
All in all I really enjoyed the experience and would love to get better at it.
Thanks in advance for any responses.