Many years ago when local inspectoprs of taxes made visits to their local, a publican had an afternoon meeting with a tax inspector in his pub.
The publican had been claiming tax relief in respect the upkeep of his 'guard dog' but the taxman was unwilling to concede that this was acceptable.
The publican replied that upstairs in the pub were both the dog and the lunchtime takings.
He invited the taxman to go upstairs, on his own, and if the taxman returned with the takings the publican would agree to add back the disputed expenses.
The taxman's response was to allow the expense in full.
My thanks to Barry Jefford of George Hay, Chartered Accountants, who told me this story many years ago, after he heard it from his client, being the publican in question