I think you can just spend one day at Jiuzhaogou to visit the main spots Multi-coloured Lake, Nuorilong Fall, Long Lake and the Pearl Beach. For the other day, you can enjoy yourself at Huanglong near to Jiuzhaigou. There are ATM at the customers' center of the entrance and Yinxin Hotel. I think you can take some cash with you for the transportation or buying something at small stands as well as the credit card used at the acceptable places.