Some byc'ers use a 50/50 solution of plain white vinegar and water to spray everything down with.
Some use Oxine solution. It's available at
amazon.com.
Properly diluted with water, Oxnine can be used to spray everything down with and is completely safe and non toxic to people and chickens, but will sanitize the whole coop.
To completely eliminate all contamination of virus, fungus, and infection, Oxine can be activated with citric acid and then used in a fog machine to completely fog the entire coop. But that activated solution is EXTREMELY toxic to humans and chickens, and you have to wear a respirator.
I haven't used Oxine, but I just found out about it from reading someone else's post here on byc. I then read up on it by googling it. I ordered some yesterday and will dilute it with water and use it as a spray. Just as a general preventative. I'm not comfortable with the idea of activating it and making it toxic.
Read up on it and you can decide about it. Up to now, I've just used vinegar and water, and have had no mold, bacteria, or viruses. But I'm thinking I'd like to have the Oxine on hand to use as a spray, just in case I see mold starting anywhere in the coop or run.