I use
http://www.ishinecarcare.co.uk/ , which is run by an old friend.
2 buckets, both with grit guards.
Autobrite Foam Lance, with autobrite super snow foam (magifoam is not pH neutral so will strip off some of your existing protection stuff if you leave it on too long)
Rinse off with pressure washer
Autoglym shampoo with merino wash mitt
Rinse off
Dry with towels
When needed, Hellshine Abyss spray sealant
A few weeks after sealant, zymol wax from 10 years ago that's still going strong
You can spend a fortune, but there's no need to. As mentioned above, most of the systems work really well now, and Halfords carries a good range - but no grit guards yet!