HMRC are implementing a Making Tax Digital initiative which will start in April 2019.
It requires your agency's business to keep your accounts in a digital format. You can then upload your tax returns online.
What you must do is supply Letmc support with a list of "Nominal Codes" which we will apply against your individual sales charge types i.e.
Charge Type - Management Fee
Nominal Code - 1009
You can then download your Invoiced Sales at the end of each month when the report is archived.