I only enroll full-timers.
I currently have 12 children ranging from 6 weeks to 5 years. All but 2 come 5/days per week and the other 2 come 4/days a week but pay the full-time rate. They are free to use the 5th day at any time.
I wouldn't have it any other way. I'm extremely lucky and the money defintely doesn't hurt