Got the job. Now i need your help

The owners have used a bleach solution on it 3 years ago with good results
They don’t feel like doing it so asked me to.
From what I have researched liquid bleach is used in a soft wash to kill mold. I was thinking if adding dome simple green as a sufragent.
While fresh wash may be a great thing for most this is only one job and I may not get another for a long time so I will use CHEMS I can get locally.