NOT LISTED FOR SALE

91 Union Ave Islip, NY 11751

Estimated Value: $728,000 - $775,000

4 Beds
2 Baths
2,481 Sq Ft
$300/Sq Ft Est. Value

Last Sold August 13, 2025

Last sale price $750,000 $302 Per Sq Ft

Est. 1% decrease in value since last sale

Current estimated payment $4,867/month

18 Days on Market

Highlights

  • Colonial Architecture
  • Granite Countertops
  • Eat-In Kitchen
  • Islip High School Rated A-

About This Home

As of August 2025

This beautifully restored Colonial is located in a prime residential block, just south of Montauk and in close proximity to the vibrant Main St. area, offering a variety of restaurants, charming boutiques, and local beaches. This home features a bright and open floor plan, with an updated eat-in kitchen and stainless steel appliances. With 4 spacious bedrooms and 2 full baths, this property offers comfort and style. The meticulously maintained grounds include new brick pavers and a charming gazebo, perfect for outdoor relaxation and entertainment. A true gem in a highly desirable area!

Last Agent to Sell the Property

Michael Watts

Michael J Watts & Assoc Inc Brokerage Phone: 631-650-9933 License #10311200426 Listed on: 03/17/2025

Home Details

Home Type

  • Single Family

Est. Annual Taxes

  • $12,163

Year Built

  • Built in 1870

Lot Details

  • 9,148

Parking

  • 2 Car Garage

Home Design

  • 2,481 Sq Ft Home
  • Colonial Architecture
  • Frame Construction
  • Cedar

Kitchen

  • Eat-In Kitchen
  • Granite Countertops

Bedrooms and Bathrooms

  • 4 Bedrooms
  • 2 Full Bathrooms

Schools

  • Maud S Sherwood Elementary School
  • Islip Middle School
  • Islip High School

Utilities

  • Ductless Heating Or Cooling System
  • Heating System Uses Natural Gas

Additional Features

  • Washer
  • 9,148 Sq Ft Lot

Listing and Financial Details

  • Assessor Parcel Number 0500-396-00-04-00-073-000

Home Details

Home Type

Single Family

Est. Annual Taxes

$12,163

Year Built

Built in 1870

Lot Details

0

Parking

2

Listing Details

  • Property Type: Residential
  • Architectural Style: Colonial
  • Property SubType: Single Family Residence
  • Year Built: 1870
  • Attribution Contact: 631-650-9933
  • Carport Y N: No
  • CurrentPrice: 750000.00
  • MlsMajorChangeType: Sold
  • CurrentPrice_By_LivingArea: 302.29746
  • ListPrice_By_LivingArea: 294.23579
  • ListPrice_By_OriginalListPrice: 1.00000
  • ListPrice_By_LotSizeAcres: 3476185.7143
  • LivingAreaSearchSqFt: 2481.00
  • CurrentPrice_By_BuildingAreaTotal: 302.29746
  • Special Features: None
  • Property Sub Type: Detached

Interior Features

  • Appliances: Refrigerator, Washer
  • Interior Amenities: Eat-in Kitchen, Granite Counters
  • Full Bathrooms: 2
  • Total Bedrooms: 4
  • Living Area: 2481
  • Basement YN: No

Exterior Features

  • Construction Materials: Cedar, Frame
  • Waterfront: No

Garage/Parking

  • Garage Spaces: 2
  • Garage: Yes

Utilities

  • Cooling: Ductless
  • Heating: Natural Gas
  • Sewer: Public Sewer
  • Utilities: Electricity Connected, Sewer Connected, Trash Collection Public, Water Connected
  • Water Source: Public

Condo/Co-op/Association

  • Senior Community: No
  • Association: No

Schools

  • Middle School: Islip Middle School

Lot Info

  • Lot Size Acres: 0.21
  • Lot Size Sq Ft: 9148
  • Parcel Number: 0500-396-00-04-00-073-000
  • Property Attached: No

Rental Info

  • Lease Considered: No

Tax Info

  • Tax Annual Amount: 12163
  • Tax Year: 2024

MLS Schools

  • Elementary School: Maud S Sherwood Elementary School
  • High School: Islip High School
  • Middle School District: Islip

Ownership History

Date Name Owned For Owner Type

Purchase Details

Listed on
Mar 17, 2025
Closed on
Aug 8, 2025
Sold by
Zerbo Edward
Bought by
Taylor Maggie
Seller's Agent
Michael Watts
Michael J Watts & Assoc Inc
Buyer's Agent
Michael Watts
Michael J Watts & Assoc Inc
List Price
$729,999
Sold Price
$750,000
Premium/Discount to List
$20,001
2.74%
Views
66
Current Estimated Value
$745,233

Home Financials for this Owner

Home Financials are based on the most recent Mortgage that was taken out on this home.
Estimated Appreciation
-$4,767
Avg. Annual Appreciation
-1.66%

Purchase Details

Closed on
Feb 12, 2016
Sold by
Walnut Lg Corp
Bought by
Zerbo Edward

Home Financials for this Owner

Home Financials are based on the most recent Mortgage that was taken out on this home.
Original Mortgage
$363,375
Interest Rate
3.65%
Mortgage Type
New Conventional

Purchase Details

Closed on
Jul 16, 2015
Sold by
Holmes Virginia E and Koelbel Virginia E
Bought by
Walnut Lg Corp

Home Financials for this Owner

Home Financials are based on the most recent Mortgage that was taken out on this home.
Original Mortgage
$172,000
Interest Rate
3.97%
Mortgage Type
New Conventional
Source: Public Records

Range of Values:

--
Value Increase
--
Percent Increase
--
Adjusted for Inflation
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Average Value
Not Available
List Price
Sold Price
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Home Values in the Area

Source: Public Records

Average Home Value in this Area





Source: Public Records

Purchase History

Date Buyer Sale Price Title Company
Taylor Maggie $750,000 --
Zerbo Edward $427,500 None Available
Walnut Lg Corp $180,000 Wfg Title
Source: Public Records

Mortgage History

Date Status Borrower Loan Amount
Previous Owner Zerbo Edward $363,375
Previous Owner Walnut Lg Corp $172,000
Source: Public Records

Property History

Date Event Price List to Sale Price per Sq Ft
08/13/2025 08/13/25 Sold $750,000 +2.7% $302 / Sq Ft
04/04/2025 04/04/25 Pending -- -- --
03/17/2025 03/17/25 For Sale $729,999 -- $294 / Sq Ft
Source: OneKey® MLS

Tax History Compared to Growth

Source: Public Records

Tax History

Year Tax Paid Tax Assessment Tax Assessment Total Assessment is a certain percentage of the fair market value that is determined by local assessors to be the total taxable value of land and additions on the property. Land Improvement
2024 $11,541 $34,800 $10,400 $24,400
2023 $11,541 $34,800 $10,400 $24,400
2022 $9,885 $34,800 $10,400 $24,400
2021 $9,885 $34,800 $10,400 $24,400
2020 $9,481 $34,800 $10,400 $24,400
2019 $9,885 $0 $0 $0
2018 -- $34,800 $10,400 $24,400
2017 $10,484 $34,800 $10,400 $24,400
2016 $9,727 $32,350 $10,400 $21,950
2015 -- $32,350 $10,400 $21,950
2014 -- $32,350 $10,400 $21,950
Source: Public Records

Agents Affiliated with this Home

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Map

Source: OneKey® MLS

MLS Number: 836404

OneKey® MLS

APN: 0500-396-00-04-00-073-000