{ACCOUNT BALANCE} is a printer template tag intended to use in printer templates. There is a chicken-egg problem here. As printer template tags processes before report tags passing a report inside printer tag does not work.
{ACCOUNT TOTAL} gives account transaction amount total in given work period. You can filter by account or transaction type. Credit gives credit total. Debit gives debit total.
Maybe there is no credit transaction in active work period so it returns 0.
We can solve that no problem. As I’ve said before I don’t have much hotel experience but when thinking logically it seems like to me you don’t need to make customer account transactions until customer makes a payment. Why don’t you just operate room account?