A zero balance means the invoice charges have been paid.
More than 1 means more than 1 is owing on the invoice charges
More than 10 means more than 10 is owing on the invoice charges
More than 100 means more than 100 is owing on the invoice charges
More than 1000 means more than 1000 is owing on the invoice charges
Less than 1 means less than 1 is owing on the invoice charges
Less than 100 means less than 100 is owing on the invoice charges
Less than 1000 means less than 1000 is owing on the invoice charges