It takes about 3 hours to drive from Dublin to Doolin, 4h if you count a break for food. That would put us in Doolin at 2pm at the earliest, 3pm would be safe.
Family roundtrip ticket costs E125.
Inis Mor: 3 boats on July 30: 9am, 11am, and 1430
Inis Oírr: 5 boats on July 30: 10am, 11am, 1pm, 1430, 1715