Having zero clue of what kind of soap or what else you have over there to your disposal for cleaning.. however, I have had luck with vegetable natural fat household soap. I mix 1 third of soap with no more than two thirds of water, sometimes 50/50. Spray on and let it nearly dry on. Then I use a stiff brush or scrub to clean. For more stubborn marks I’ve also used car polish.
The more the soap is alcalic and removes fat the more difficult to maintain afterwards. And it will soon get a matte finish which again attracts dirt.
The fat vegetable soap leaves some fat behind and softens stains. A bonus is when you rinse off with water afterwards, the surface repels water drops like a newly polished car. [big grin] (I use the same soap on my car, boats or whatever. All the plastic and rubber looks very good even long after wash)
Edit: And, there’s another thing: it’s the temperature of the water that cleans as well, my systainers from my used Festool’s buys I have done in my bathtub - but I’m kinda single for the moment - so there you go [big grin] [big grin]