Sounds like you have been treated par for the course. Those officials at the PSB are a different breed from ordinary Chinese. I suspect the PSB themselves were the hardest to deal with when compared to the police stations you visited. The thing is that without the accommodation paperwork being properly completed and stamped, you could end up overstaying and being fined 5,000 RMB/day if that hasn't increased. Delays can occur at police stations if the boss is out. He is the only one with the stamp, which is kept in a padlocked drawer, and nobody else has the key.