You can go to the PWNA website and purchase a book thru them to get a better understanding. There webiste is PWNA.org and then to there store site. In there for a few bucks you can go to there store section and purchase a book. You can also get certified thru them which is a huge market advantage.
Another guy that teacher wood restoration and basic powerwashing thru class work and if you call him mention my name. His name is Matt Johnson who owns a contracting business and he also teaches classes and on top of that he owns a Hydrotek distributership. So he is a true entrepreneaur. He can be reach at http://www.pwscleaning.com/Multi%20Unit%20Cleaning.html I hope this helps some. I would suggest you call Matt and he can at least give you much needed info. Good luck
Another guy that teacher wood restoration and basic powerwashing thru class work and if you call him mention my name. His name is Matt Johnson who owns a contracting business and he also teaches classes and on top of that he owns a Hydrotek distributership. So he is a true entrepreneaur. He can be reach at http://www.pwscleaning.com/Multi%20Unit%20Cleaning.html I hope this helps some. I would suggest you call Matt and he can at least give you much needed info. Good luck