The book was being updated in real-time with all relevant information, be it about the people holding titles or about other more basic stuff.
'Where is-'
Hao Xuan skimmed through a couple of pages but as if the book could read his mind, it took control and automatically flipped over to the information he needed.
At the very top, it mentioned that the official currency used within the sanctum was something called the 'Cursed Gold' and all the prices he saw were also in it.
Simply put, Cursed Gold or 'CG' was created when normal gold coins were marked and then 'blessed' by the 'Servants' of each of the Nine, imbuing a very small portion of their energies into it.
There was obviously much more included in the process but it could be summarized this way. This was how the sanctum maintained control over its assets.