A recurring mandate dispute means the mandate was never clean.

The usual mistake with a mandate dispute that keeps coming back is to blame the people, when the fault nearly always sits in the document. A clean mandate settles whether it is sole or open, when it starts and when it ends, the asking price and the commission, and whether the seller may sell to a buyer they find themselves without owing the agent anything. Each of those points can be argued later if it was left vague, and they are left vague more often than anyone admits. A blank where the expiry date should be. A sole mandate signed by one spouse on a house registered to both.

The arguments that follow are predictable. Sellers who find a buyer through a friend tend to believe no commission is due, because the agent never brought anyone. Agents point to the sole mandate, which says commission is payable on any sale during its term, and sometimes both sides then discover the term was never filled in. Each side reads the gap in its own favour, and both are being honest. The sale may close, but the argument returns at the next listing. The gap was there on the day of signing, waiting for someone to need it.