I do watercolor illustrations mostly and the revisions I offer at at sketch phase. I usually send the pencil sketch and maybe a small color for confirmation. But too many times the client changed his mind when seeing the final artwork and asked me to change things. [even if its almost impossible on a hand painted illustration but I can manage to do it]
The thing is if they should cost money or not. If I tell the client “only 3 free revisions, the rest cost money” they tell me “well I paid for the illustration but I dont like it. I want you to change it to my liking so I dont see why i should pay more”
2 years on fiverr and still dunno how to respond to that. I usually hope clients wont ask the impossible from me , just minor changes. But I also had these clients demanding me to redraw the whole thing and then they still didnt like it and left a 3 star review.