Almost like talking oil with an car guy. Lots of options and opinions.
It is a full body paint, so any good quality automotive wash will work.
How do you plan to apply the soap? Bucket with a long carwash brush? Foam sprayer from a garden hose or pressure washer?
I like Meguiares products. For the past 5 years or more, I have been using their Ultimate Wash and Wax. It does a good job cleaning. Wax part of it, its so so does not last long.
When the bottle is empty, I am thinking about trying their new Snow Foam Xtreme.
https://www.meguiarsdirect.com/megui...fo.description