Bifengxia is in Yaan City which is about 140km away form Chengdu. You may come to Chengdu by air and go there by car.
The price of holding a baby panda at Chengdu Giant Panda Base ia CNY1,000. Some of the tourists I guided have done that before.Though I think it's a little bit expensive, but from their smlile, I know it's really worth.
Hope you have an amazing trip in China!

I visited the Bifengxia Panda Base a couple weeks ago, and you also have the option of paying 500 yuan to sit next to/touch a young (1-2 yrs) panda--my friend and I were only allowed a few pictures, possibly because there were others in our group who paid more to do more, but it's still cheaper than the cost of a similar encounter at the center in Chengdu.