In the Birthright box set under the section for domain maintenance it
indicates for each Castle a regent controls the cost is 1 GB. However in the
Endier player's secrets folder ,while explaining the maintenace costs for
that realm, it indicates that castle Endier(a level 6 castle) has a
maintenance cost of 6 GB.Which seems to indicate that the cost to maintain a
catsle is not 1 GB but rather 1 GB per level. What do you think?