8Where any supply of services is treated by virtue of section 8 as made by the person by whom they are received, the value of the supply shall be taken—
(a)in a case where the consideration for which the services were in fact supplied to him was a consideration in money, to be such amount as is equal to that consideration; and
(b)in a case where that consideration did not consist or not wholly consist of money, to be such amount in money as is equivalent to that consideration.