Some notes about the GST ledger.
Firstly, assuming that there was no Agent's commission, AND that no one-off ledger payments were made during a month, then the GST total for the month should be 15% of all the other fee amounts.
However, if there was a one-off ledger payment (e.g. to pay for a casual advert, or to refund fees), then it is common for a user to take the money from a fee account (Management Fees) but not to also take some from the GST ledger. This would throw out the GST balance.
A further complication comes in with Agent Commissions.
As transactions are processed, part of the fees are separated out for each agent earning commission, BUT part of the GST will only be allocated to the Agent if his Agent record holds a GST number - otherwise the agent will only get the Fee amount and the GST portion will remain in the GST ledger.
Again, if no one-off payments have been made out of the ledger fee accounts, the total of all fee balances PLUS the total of agent commissions balances can be used to check the GST balance - assuming no agents were getting GST.
If some agents are being allocated GST money as well as commission, and some are not, then it is difficult to determine the exact GST amount. However, right clicking the GST ledger and doing a details report will show all the GST, and at the end how much of it was allocated to Agents.
Because of the various possibilities, we suggest that you add all fee balances plus the GST balance plus all agents' money, then divide by 9 to get the GST figure.