Is there a bus from Chongqing to Jiuzhaigou? Or maybe a car hire service to drive us there?

Yes, you can take a direct bus to JZG from Chongqing Bus Station near Chongqing Railway Station. The bus departs at 8:00, and the fare is CNY 216 per person.

The distance is about 404 miles (650 kilometers). It may be costly to hire a car. Hence, you are advised to use public transport. Have a nice trip!