18451 W Observatory Rd is a 3,188 square foot house on a 5.81 acre lot with 5 bedrooms and 3.5 bathrooms. Based on Redfin's New Berlin data, we estimate the home's value is $998,372.
Single-familyProperty Type
2017Year Built
5.81 acresLot Size
$313Est. Price/Sq.Ft.
Source:Public Records
Redfin Estimate
$998,372
$6,000 since August
Recently sold homes
Estimate history
Homes for sale
This home's estimate is 43.9% higher than the average sale price ($694K) of 6 comparable homes.
As the MLS and public records start to fill up, we'll list the details here.
Year
Property tax
Land + Additions
Assessment*
2025
$10,095 (+6.2%)
$117,600 + $700,600
$818,200
2024
$9,502 (+4.4%)
$117,500 + $700,600
$818,100
2023
$9,102 (−3.3%)
$70,921 + $538,300
$609,221
2022
$9,415 (+5.6%)
$70,921 + $538,300
$609,221
2021
$8,917 (+8.0%)
$70,921 + $538,300
$609,221
2020
$8,258 (−3.1%)
$70,921 + $538,300
$609,221
2019
$8,522 (+7.7%)
$70,900 + $489,700
$560,600
2018
$7,910 (+4,463.0%)
$71,000 + $430,900
$501,900
2017
$173
$10,100
Tax history for 18451 W Observatory Rd
Year
Property tax
Land + Additions
Assessment*
2025
$10,095 (+6.2%)
$117,600 + $700,600
$818,200
2024
$9,502 (+4.4%)
$117,500 + $700,600
$818,100
2023
$9,102 (−3.3%)
$70,921 + $538,300
$609,221
2022
$9,415 (+5.6%)
$70,921 + $538,300
$609,221
2021
$8,917 (+8.0%)
$70,921 + $538,300
$609,221
2020
$8,258 (−3.1%)
$70,921 + $538,300
$609,221
2019
$8,522 (+7.7%)
$70,900 + $489,700
$560,600
2018
$7,910 (+4,463.0%)
$71,000 + $430,900
$501,900
2017
$173
$10,100
*Taxable value of land and structures on it ("additions") is determined regularly by local assessors and does not affect market price.
Zoning
C-1
Upland Resource Conservancy District
The C-1 Conservancy District is intended to prevent the destruction of valuable natural and man-made resources and, in particular, woodlands, wetlands, wildlife habitat areas, perennial and intermittent streams, major lakes, floodlands and shorelands, significant water recharge and discharge areas, prairies, recreational and scenic areas, natural scientific areas, areas with poor soils or high groundwater, and areas of steep slopes, including primary environmental corridor, secondary environmental corridor and isolated natural resource areas. Regulation of these areas, including environmental corridors, should serve to control erosion and sedimentation and to protect the natural resource base and promote and maintain the natural beauty of the area as well as the health, safety, and welfare of City residents.
Permitted uses
Include but are not limited to:
Agriculture
Housing-Single unit
Infrastructure
Agriculture-Cropland
Park & open space
Wilderness
Property details
Interior
Basement Information
Basement Sq. Ft: 3,701
Basement Finish: Finished
Bathroom Information
# of Full Baths: 3
# of 1/2 Baths: 1
Fireplace Information
Has Fireplace
Room Information
# of Rooms: 8
Exterior
Exterior Information
Building Style Type: Ranch
Property Information
Living Sq. Ft: 3,188
Ground Floor Sq. Ft: 2,529
Building Sq. Ft: 6,230
Legal Description: LOT 2 CSM #11499 REC 10/31/2016 DOC #4242364 BEING A REDIVISION OF PT OF LOT C CSM #1783 VOL 12 P165 & LANDS IN THE SW .25 OF THE NW.25 SEC 21 T6N R20E CONS EASE DOC #4258216 REC 01/17/2017 DOC #4487201 06/25/2020
Lot Information
# of Buildings: 1
Land Sq. Ft: 253,084
Legal Lot Number: 2
Municipality Name: NEW BERLIN CITY
Acres: 5.81
Zoning Code: R1
State Use Description: RESIDENTIAL
Utility Information
Water Service Type: Well
Utility Type: Gas Public
Financial
Assessor Information
Assessment Year: 2025
Tax District County: NEW BERLIN CITY
Public facts
Beds: 5
Baths: 3.5
Sq. Ft.: 3,188
Stories: —
Lot Size: 5.81 acres
Style: Single Family Residential
Year Built: 2017
Year Renovated: —
County: Waukesha County
APN: NBC 1234989007
Home facts updated by county records on Jun 15, 2026
Around this home
Schools
Ronald Reagan Elementary School
Public PreK-6 • Assigned • 0.7mi
6/10
New Berlin Middle/High School
Public 7-12 • Assigned • 1.5mi
9/10
Provided by GreatSchools
Lifestyle
Provided by Walk Score and Local Logic
Climate risks
1/10 Flood Factor
Minimal risk of a flood reaching the building in the next 30 years
3/10 Fire Factor
0.31% chance of being in a wildfire in next 30 years
2/10 Heat Factor
7 days above 100° expected this year, 13 days in 30 years
2/10 Wind Factor
Minor risk of severe winds over next 30 years
2/10 Air Factor
1 unhealthy days expected this year, 1 days in 30 years
Provided by First Street
Historical weather
New Berlin, WI • 53146
Average low and high temperatures (°F)
26
12
34
18
50
30
59
39
66
46
79
60
82
64
78
61
76
56
65
46
47
34
33
20
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Sun exposure
In this area, properties receive around 10 hours in
June and 3.4 hours in December, placing it below the
U.S. average for solar exposure.
10 hrs
3.4 hrs
JuneDecember
Provided by Shadowmap
Estimated sale price
$949,000 – $1.15M
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