I have never used a pressure washer before. I am considering buying one rather than renting, but I don't know how much power I need. I have a two story house. I read that you should not use the washer while standing on a ladder, so I would think that I need one powerful enough to reach the second story, but I don't want it to crack/destroy the vinyl siding. Will a electric washer rated at 1600 psi do the job?? Suggestions??