The complaints assessment committee said it was difficult to comprehend how someone using care, skill and competence could have sent such an email.
"The offensive email...falls short of the standard that a reasonable member of the public is entitled to expect from a reasonably competent licensee," the committee said.
Clarke said the email should not detract from any of the work that was done prior to it being sent and described her disappointment at the complaint by the vendors being escalated to a hearing.
Clarke added, in a written submission to the committee, that her conduct was unintentional and was not motivated by gain or intended to disadvantage anyone.
However the committee noted that the vendors were that they were not entirely happy with the service even before the email was sent.
"Part of Mr and Mrs V's complaint was that they were not kept informed of the (sale) process."
The committee censured Clarke and ordered her to pay the vendors $5000 and apologise to them in writing.
"The committee can only hope that that is not the tone that Ms Clarke normally uses for her internal correspondence".