looks like polar pre-wash is not too expensive 2.5l/£8.4 so maybe I would use 100ml ... but, usual strategy, like screen wash, use what seems reasonable -
regularly use up rejected hair shampoos, in a two bucket wash.
... but ? you are allowed to clean cars in underground parking ?
regularly use up rejected hair shampoos, in a two bucket wash.
... but ? you are allowed to clean cars in underground parking ?