We are looking for the best way to travel from Longsheng (Ping'an) to Fenghuang.

I didn’t find the information of your route, but I once hired a local car from Longsheng to Guilin and the fare was RMB 400.
Anyway, here is the public transport:
To Fenghuang: take a bus from Longsheng Genaral Bus Station to Guilin. It takes about 2h and RMB 35; then, take a bullet train from Guilin Station to Changsha South; and it takes 3-4h, RMB 181.5 for a second class seat; after arrival, take a bus from the station near the South station to Fneghuang, and it takes 6-6.5h, RMB 150 or so.
To Zhagnjiajie: take a bus from Fenghuang General Bus Station to Zhangjiajie directly. It takes about 3h, RMB 80.

Thank you so much Amy.

Well, I guess for the journey from Fenghuang to Zhangjiajie we will definitely take your suggested bus. That sounds very good.

From Longsheng to Fenghuang: did you just took a local taxi and asked or did you booked via a provider? Do you remember the name? Looks like with public transport it doesn`t make really sense as it would take almost a whole day (and we came 1 day before from Guilin).

We found the local car near the Longsheng General Bus Station, but it seemed the driver didn’t understand English. We traveled with a Chinese friend, and he helped us a lot. So, I guess it may be hard for you to find a car. If the public transport is not available, I think it’s better to take the taxi arranged by the hotel. It’s much easier and safer. Nice trip!