I use baby powder to cover on show day when in a rush
Not sure where you are from so I'm not sure what you call it but I've always found blue washing up liquid (dish soap?) works a treat and is a lot less expensive than the horsey versions!
Glow white purple shampoo it is mandatory for anyone who owns a grey…
I've heard that tomato sauce is said to work really well on a white horses tail ( not sure about their body though) to get it white again, I've never personally tried it but I've heard it works, not sure how it does though.
I can't remember the name of the brand but, it is purple and the brand starts with a "V" I think it's called vetrolin or something. I used to have a paint quarter horse, and it worked miracles!