when a client books online and chooses the haircut service first and then the color, it allows them to book the appt as haircut first and color second with no processing time and it screws up the schedule. This should be flagged and the client shouldn't be able to book the appt this way.
Also, pop-ups would be nice to show any client notes before checkout. Some clients have special pricing in notes, but it gets overlooked without having a pop-up show before checkout