I went to Dujiangyan Base last year and did the volunteer program and that cost me 700 RMB. I got to feed the panda, clean the habitat, make panda cake, and got a shirt. But you have to apply for it and have a doctor fill out a health form. I also paid an additional 1800 RMB to hold a panda and get a picture taken with it. That doesn't require an application or health form.
The whole experience was expensive, but it's worth it. How many people in the world can have such an experience?
Dujiangyan Base is more remote and definitely less crowded. The only disappointing thing is that they didn't have any baby pandas there to look at.