The vendor told the Herald he had brought family members to viewings and asked Bayleys real estate agents for a window to be replaced and picture hook holes filled in.
He even visited a neighbour to discuss trees on the property and arranged to have a barbecue with him once the sale went through.
A pre-auction offer was written up with conditions including a 10-day settlement period, which the owner agreed to.
The auction was held and the man bid via phone. There were no other bidders in the room and the property sold to the man for $1,175,000.
But the owner said that when it came time to pay the agreed 10 per cent deposit, the man kept making excuses, blaming failed transactions on bank error. Eventually, he stopped answering his phone.
The owner had already bought another home, but said some people would not be able to raise enough money for a new house without selling their current property.
"The ramifications of what he could do to someone else are quite huge ... If you think you've sold it, and you go unconditional on another property, then the whole chain can become a bit of a nightmare."
In another case, the man viewed a four-bedroom clifftop weatherboard house in Army Bay, with a valuation of $920,000.
Ray White chief executive Carey Smith said the man told the agent he wanted to make an offer and a transaction sheet was drawn up. But when the company contacted a lawyer the man had nominated, he told them he did not know who the man was.
It is understood Harcourts has been dealing with the man over two other properties - a sprawling mansion worth $1.65m and a set of yet-to-be-built units worth $449,000 each.
The Herald contacted the man last night and he confirmed he had looked at the four homes. He claimed he had intended to pay for the Army Bay property and had asked the real estate agent for an account number, but the agent was "hounding" him all day, so he withdrew the offer.
He said he wasn't sure what had happened with the Manly apartment.
"I'm just a 23-year-old young dad, looking after his f****** family, that wanted to buy a couple of houses."
Real Estate Institute chief executive Helen O'Sullivan said bank credit checks would prevent anyone getting a mortgage without a signed sale-and-purchase agreement.
"Maybe it's a Walter Mitty-style person who wants to imagine themselves buying such properties and then disappears when they actually have to come up with some cash."
Bayleys has wiped the auction fees for the Manly vendor but if this hadn't happened, Ms O'Sullivan said the owner could have pursued the man for damages such as the cost to re-market and re-auction the property.
The pre-auction agreement was legally binding and the man had failed to complete on a contract of obligation.
The owner could also pursue the man for the balance if the property sold for less than what he had bid, Ms O'Sullivan said.
Real estate agents could ask to see copies of bank statements but could not force a person to show one.
A Bayleys spokesman said: "It appears that we, along with other agencies in the area and a handful of vendors, have all been duped by this hoax 'buyer'.
"His actions have been frustrating and time wasting for all concerned, to say the least. We are confounded over the hoaxer's motivations, as there appears to be no personal gain of any sort."
