Tibet permits in Xi'an?

Hello Pros,

We're in Xi'an for a few days before heading out west (not Xining) and then down through the desert into Golmud and from there on to Lhasa. Therefore, we're trying to organize the Tibet permit here in Xi'an, but the hostel we're staying at only does it for 800 Yuan each, which we thought was quite expensive. Any suggestions on other places you've gone to or heard about going to in the city to get a better price?

One more query - has anyone had luck getting a hard-sleeper from Golmud to Lhasa, or is this just a pipe dream? If so, how much does the hard-sleeper cost, and if not, how much does a hard-seat cost? Thanks for your time, and we look forward to soaking up your wisdom.