I tend to ask if they want this or that done foc, there was a couple arguing over the front wall which was filthy but the guy thought it looked rustic and the wife agreed with me. You could do something like clean the cat without asking, for them to be annoyed about it as they liked the way something looked.
Watched a mark cave video and he was cleaning a wall whilst saying that it hadn't been included in the price nor was there any agreement for it to be done and he's saying it's "just good customer service". Whilst I'm watching I'm thinking about the couple arguing in the street over the dirty wall.