I require mix revision request limits. And then I submit them fast until they run out and usually they won't pay for another revision and then I'm out of there! I find that those type of clients that want to keep making it something it's not, and don't take your input are not the type of quality clients that you'd want to maintain a long relationship with. I submit my mix and hope they don't come back haha. I love working with artists that understand the the work they have to put into their song in every single aspect from sound design, production, vocal performance, feeling, quality, the right mic, the right room, the right vocal take. Sooo so much. That makes me love what I do and keeps me there.