Listed by Ray White's Randall Kemp and auctioned by Cooley director Damien Cooley, the property received a lot of pre-sale buzz from buyers.
Around four or five buyers registered for the auction prior to the sale, which was expected to result in around $4 million.
This modern home appeals to families and buyers looking to entertain guests in the courtyard, which has an integrated barbecue, pizza oven and Jacuzzi.
However, despite its strong location and features, the property did not live up to the owner's expectations and did not get the result all parties wanted on the day.
"The auction was very competitive," said Mr Cooley.
"The opening bid was $4 million and it finally sold for $4.9 million."
"At the end of the day, some owners were nervous about their next move and made sure they sold their dream home for the price they wanted."
Mr Cooley believes that sellers often have to carefully weigh their options when selling a property, taking into account factors such as settlement periods, moving costs, renovations and paperwork.
"The market is generally good, but there are some properties that don't sell on the day and this is unfortunately one of them."
While the Twin Bays did not turn out as well as hoped, there were other sales that were successful.
A property that has been in the family for three generations sold for $116,000 above the reserve price.
The three bedroom and one bathroom property at 43 Prospect St Erskineville was once the home of a professional boxer named Fargo Young - who competed in 262 fights.
Listed through Ray White's Sean Stoker, the auction saw 10 registered bidders, four of whom were active bidders.
Almost all of the bidders were builders, but the highest bidder was an investor who saw it for the first time on Thursday night and was ready to renovate it and rent it out," Mr Stoker said.
The property was eventually sold for $1.416 million to another family who wanted to renovate and redesign it.
"It was in a great location right next to the village of Erskineville, which is rated as one of the best suburbs in NSW and has been in high demand ever since.
"Plus the property has great potential to increase in value."
Finally, Rouse Hill also set a new price record, with a five-bedroom property fetching $446,200 more than its previous price.
The auction at 12 Cleveland Close saw 13 bidders place more than 68 bids throughout the competitive process, which was conducted through Stu Benson of Benson Auctions and presented to the market through Ray White's Shiv Nair.
Bidding started at $1.9 million and eventually sold for $2,816,200 - a $100 bid being the final impetus for the successful buyer.
Mr Benson said they were immigrants from The Ponds, a neighbouring suburb of Rouse Hill.
"The fact that 13 registered bidders had expectations of $2 million or more for the Rouse Hill property shows that there is now confidence in real estate in the Hills. It's an investment."
"You have to remember that once Phase 2 of the Metro Line is operational, you can hop on a driverless train and go straight to Barangaroo - it has changed everything and will continue to change the fortunes of property owners in the Hills."