For users of Karcher Power washers this is a reasonable price of £6.39 for 6 Litre bottles of Karcher Universal Cleaning Agent. Postage is £4.95
Most On-Line Sellers I have found only sell it in 5 Litre bottles and at a price similar to this or higher.
Not a fantastic saving but if you use a lot of the cleaning agent it is better value as the postage is still £4.95 no matter how many bottles you buy.
This cannot be collected in store but must be delivered.