Well, you could seek orders at NCAT to prevent the chair putting the posters on common property, backed up by a request for interim orders.
Or you could send the chair a note saying that if your unit doesn’t reach the reserve price, based on Real Estate experts’ advice that no-pet apartments get 5-10 per cent less in today’s market, you will sue them for the difference unless they cease and desist.
By the way, the 5-10 per cent is made up – but I bet you could get your RE agent to say it.