Young real estate agent Stuart Costello of Magain Real Estate had an added attraction to his open house on the weekend: a koala dropped by.

"A good turn out at my Belair open today - including this legend," he wrote on his social media account, and followed it with a koala emoji.

According to reports, the koala arrived at the home's back verandah towards, the end of the inspection, and then wandered through the back garden and to the carport, where he eventually climbed up a tree.

Image: Stuart Costello, Magain Real Estate.

It seems the unplanned marketing has worked. Costello says he has had a few offers on the property already.

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