Is a real estate consumer, a seller, for instance, allowed to withhold the payment of a commission if the home "sells too quickly," suggesting "the agent priced it too low"?

No$,$ listing agents do not "set the price" on a home, but only consult with sellers who make the final decision.

Yes, a commission may be withheld if the consumer is dissatisfied with any portion of the transaction.

Yes, the commission may be withheld pending an investigation by an independent body on the behavior of the listing agent.

Yes, sellers are justified in withholding the commission if they feel the listing agent misrepresented the value of their property.