What is the starting point for an estate agent’s commission?

It is clear from Kerans J.’s discussion that the starting point must always be the words of the listing agreement. Indeed his judgment began with the following quotation from Harman L.J. in Wilkinson v. Brown [1966] 1 All E.R. 509 at 510: This is another of these difficult cases about agent’s commission, and I think that it is desirable that the numerous examples appearing in the reports should not be added to because each of them depends entirely on the exact terms of the document in question where, as here, it is a written document. Theories about what estate agents ought or ought not to receive or what it is just that they should receive are all by the way . . . It comes to this in the end, that before it is found that the commission is payable, the court must be satisfied that the condition on which it is payable has been fulfilled. There is nothing more in it than that.