Yeah, they did charge extra 2000-2500 for that. But I'v been watching it throughout the process ( Because I'm so particular on what what they do to my vehicle), and they did use the water gun after spraying off some chemical. And I normally do my services at C*rePo*nt Pannipitiya where it's spacious and less crowded than the Thalawathugoda branch where I did this particular service. and not that much satisfied with their respect to the vehicles at that T'wathugoda branch.
And thanks again for all your ideas. The reason for not to do my services at T*y*ta L*nka is that sometimes they use SAE 5-30 for hybrids, when they run outta SAE 0-20 oil which is the recommended oil for hybrids.