Bit of an odd one for you!
This client never paid me. It was agreed that I'd spend half a day improving a pie chart graphic that was to be the core of her brand and also to create a brand concept that could adapt alongside. You can see her existing pie chart here: https://makingartmakingmoney.com/course-1-accomplishing
The brief was to base colours on CMYK and to look a bit Museum/art gallery-esque.
So I sent over this. She wasn't happy. At this point I was beyond half a days work. I kept going, in good faith thinking I could hit the brief... and yet still wasn't designing what she had in her head. At which point, 1.5 days in I stepped away.
Didn't I get a deposit? Nope. Usually I do but we had such a good rapport on video call, and it was such a short sprint, I let trust swing it. The irony is, her business is about making money from your art business!