A rendering of a home at Country Pointe at Plainview, a development proposed for a 143-acre plot. The Beechwood Organization

Just outside Plainview in Nassau County lies the Old Bethpage Village Restoration, a diorama of historic buildings complete with costumed actors depicting a Long Island farming village from the 1800s.

It mirrors Plainview's commitment to preserving its own way of life, albeit one from a different century. Residents and elected officials say the hamlet, along with the surrounding Town of Oyster Bay, are known for their fierce defense of a suburban ideal from the post-World War II era.

"The residents of Plainview, as is true of the other communities in the town, jealously guard their borders," said John Venditto, Oyster Bay's town supervisor. "They're highly informed, highly intelligent and highly perceptive residents that really care about their community."

In the hamlet of Plainview. Mark Abramson for The Wall Street Journal

Michael Dubb, a developer, is now navigating those sentiments as he advances a bid to transform one of the last undeveloped swaths in Plainview—a 143-acre plot of trees, athletic fields and vacant buildings—into a gated community of houses, condominiums, private roads and a commercial strip. Nassau County owned the property for much of the last century.

Mr. Dubb and his company, the Beechwood Organization, are asking Oyster Bay officials to rezone the property to allow the construction of Country Pointe at Plainview, with 890 housing units and about 120,000 square feet of retail space. He proposes to leave 43 acres vacant for the town's use.

The developer, based in Jericho, Long Island, said he envisions a community where Long Island's retirees can settle near the families they raised. About two-thirds of the houses would be limited to people 55 years old or older.

Another rendering of a home at Country Pointe at Plainview, a development proposed for a 143-acre plot. The Beechwood Organization

The development also would include a clubhouse, swimming pools and other amenities. A ShopRite supermarket would anchor the commercial section.

But Mr. Dubb will have to win over a community that has been deeply skeptical of development. Charles Wang, another developer who previously tried to build on the site, faced such fierce opposition that he abruptly called off his project during public hearing seven years ago. A public hearing on the new proposal this month lasted eight hours, until about 3 a.m., attendees said.

Carol Meschkow, president of Concerned Citizens of the Plainview-Old Bethpage Community, said the project proposes to spread-out housing to Plainview at a time when other Long Island communities are moving in the opposite direction: building compact, pedestrian-friendly communities aimed at attracting and retaining young people.

"This is not smart growth," Ms. Meschkow said. "It's not a walkable community. You don't see young people settling in these single-family communities."

Mr. Dubb said he believes a demand exists among empty nesters for a condominium and townhouse community where landscaping, building maintenance and other services are covered by monthly maintenance fees of some $400 to $500.

"There's no shortage of detached single-family homes on Long Island, but there is a shortage of options for people who don't want to take care of their homes anymore," he said. Some of the houses without age restrictions could provide a foothold for newcomers to the area, he added.

Prices in the development could range from about $300,000—for one of 90 units designated "affordable senior housing"—to about $900,000, Mr. Dubb said. All the units would have two bedrooms.

Ms. Meschkow and some other residents have also voiced concerns about Country Pointe at Plainview's size, saying the influx of residents could snarl traffic or burden local schools. Mr. Dubb said the development's age restrictions mean a proportionally small number of buyers will commute to work or have school-age children.

Plainview, a hamlet of 26,000, consists of loops of low-slung, single-family houses. It is commonly mentioned alongside its neighboring hamlet to form an area called Plainview-Old Bethpage. Many of the area's families migrated there from New York City during a suburban explosion on Long Island after World War II.

A sign at Old Country and Round Swamp roads. Mark Abramson for The Wall Street Journal

"People stay," said Dona Malter, a real-estate agent who has lived in Plainview for 31 years. "There's longevity in our community. People go from starter houses in the community, and move to secondary or larger home in the community, and we as well see seniors go from perhaps a larger home to a smaller home, but staying in the community."

It is those latter residents that Mr. Dubb said Country Pointe at Plainview would cater to, but the project still requires a zoning change to proceed. The developer and town officials say negotiations could result in a more modestly sized project. Mr. Venditto said the Oyster Bay Town Board will likely vote on the zoning question by the end of the year.

Dancers in costume at the Old Bethpage Village Restoration. ZUMAPRESS

The supervisor said that, while his constituents can be tough on developers, the town doesn't deserve the reputation it has in some quarters as a place that instinctively says no to change.

"I've lived in the Town of Oyster Bay all my life, and I've found quite a bit of development goes on in this town," he said. "But it is the kind of development the residents demand to be consistent with the way they came here to live."

$485,000
63 Carriage Lane

This is a condo with three bedrooms and two bathrooms.

Property Plus: The master bath features a Jacuzzi.

Property Minus: A negative for some, the unit is on second floor.

Listing Agent: Lynda Baker of Lynda Baker Realty Corp., 516-318-6900

$649,900
4 Montclair Rd.

This is a single-family house with five bedrooms and 2½ bathrooms.

Property Plus: The home has a tiered deck with a hot tub.

Property Minus: The basement is partially finished.

Listing Agent: Dona Malter of Coldwell Banker Residential Brokerage, 516-972-7444

$898,000
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This is a single-family house with five bedrooms and 3½ bathrooms.

Property Plus: New property still under construction

Property Minus: Garage is for one vehicle.

Listing Agent: Karyn Zweback of Realty Connect USA, 917-514-8860