Mark McCullan and wife Lorraine sold their house together with neighbour Jeffrey Turner for a bumper profit.

Over 40 sites are currently on the market consisting of three or more houses being sold together, with sales appearing in new transport corridors in the northwest and once tightly held suburbs in the inner west and northern beaches.

John and Moira Bennett, Jo Butler and Richard Whitehead are among 17 homeowners combining to offer all their Manly Vale properties for sale. Picture Cameron RichardsonSource:News Corp Australia

The most recent to the hit market is a site in Manly Vale, where 17 neighbours on Kenneth Rd and Burchmore Rd are selling their homes together in a bid to attract cashed up developers.

Combined, their land could sell for anywhere between $30 million and $55 million, although no price guide has been released.

Some of the homeowners have lived in the cottages since they were built more than 40 years ago, buying them for around $80,000 or less. They stand to pocket between $1.7 million to $3 million each.

Four neighbours on 28-30 Auburn St and 3-5 Clio St in Sutherland have teamed up.Source:Supplied

Twenty-five neighbours on Ashford, Middleton and Partridge Ave in Castle Hill have listed their homes together expecting $100 million.

Split evenly, this would give them each roughly $4 million: more than double the approximate value of homes on their block.

Nearby sites on Olola St, Castle St, Carramar Rd and Worthing Ave — around the new Castle Hill Station — have seen up to 15 neighbours team up in four sales ranging from roughly $20 million to $35 million.

Four neighbours on 110-116 Wentworth Rd, Burwood have listed their homes for $10 million. Sold alone they'd each be worth only $1.6 million.Source:Supplied

But residents say the sales aren’t for profit alone. Some fear new rezoning will change their suburbs for the worse.

Homebush resident Shirley Gillett recently sold her Loftus Crescent home with her two neighbours and said she knew she’d have to sell when rezoning gave developers the green light to build nine- and five-storey buildings behind her property.

“It will be impossible to live here now,” she said. “We’ll have no privacy or sunlight. There will be dust everywhere while they build. It will just be terrible.”

This Californian bungalow is part of the Wentworth Rd sale.Source:Supplied

Developers had been knocking on her door and stuffing her mailbox with flyers for three years, she said. All but two houses on her street have now sold to developers, while eight neighbours on nearby Ismay Ave have listed their homes in a group sale.

Penrith residents Mark and Lorraine McCullan recently sold their Derby St house together with two neighbours for a total $4.2 million — pocketing them roughly $1.4 million each. Sold alone, each home would have been worth around $600,000.

Some of the 17 homes being sold at Kenneth Rd and Burchmore Rd, Manly Vale have never been listed before.Source:Supplied

Mr McCullan said they have mixed feelings about the result. “We were happy where we were, but we were bombarded by agents who said we’ll soon be surrounded by high-rise blocks. We felt forced out,” he said.

Their home took just two weeks to sell, Best Value Real Estate’s Vivek Kanwar said.

Phoenix Group agent Sandra Goodwin said residents who choose to stay in rezoned areas often pay a high penalty for not selling. “Some people don’t want to move no matter what, but when building starts they want to talk. By then, their position might not be as strong,” she said.