18300 W Observatory Rd is a 3,217 square foot house on a 10.02 acre lot with 3 bedrooms and 2.5 bathrooms. Based on Redfin's New Berlin data, we estimate the home's value is $1,124,752.
Single-familyProperty Type
2011Year Built
10.02 acresLot Size
$350Est. Price/Sq.Ft.
Source:Public Records
Redfin Estimate
$1,124,752
$0 since August
Recently sold homes
Estimate history
Homes for sale
This home's estimate is 123.2% higher than the average sale price ($504K) 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
$11,183 (+6.2%)
$188,800 + $717,300
$906,100
2024
$10,529 (+6.8%)
$188,700 + $717,300
$906,000
2023
$9,863 (−3.4%)
$174,871 + $484,900
$659,771
2022
$10,205 (+5.6%)
$174,871 + $484,900
$659,771
2021
$9,666 (−0.7%)
$174,871 + $484,900
$659,771
2020
$9,731 (−3.2%)
$174,871 + $484,900
$659,771
2019
$10,049 (−1.5%)
$174,900 + $484,900
$659,800
2018
$10,202 (+0.5%)
$174,900 + $484,900
$659,800
2017
$10,147 (−1.1%)
$158,900 + $435,800
$594,700
2016
$10,262
$158,900 + $435,800
$594,700
Tax history for 18300 W Observatory Rd
Year
Property tax
Land + Additions
Assessment*
2025
$11,183 (+6.2%)
$188,800 + $717,300
$906,100
2024
$10,529 (+6.8%)
$188,700 + $717,300
$906,000
2023
$9,863 (−3.4%)
$174,871 + $484,900
$659,771
2022
$10,205 (+5.6%)
$174,871 + $484,900
$659,771
2021
$9,666 (−0.7%)
$174,871 + $484,900
$659,771
2020
$9,731 (−3.2%)
$174,871 + $484,900
$659,771
2019
$10,049 (−1.5%)
$174,900 + $484,900
$659,800
2018
$10,202 (+0.5%)
$174,900 + $484,900
$659,800
2017
$10,147 (−1.1%)
$158,900 + $435,800
$594,700
2016
$10,262
$158,900 + $435,800
$594,700
*Taxable value of land and structures on it ("additions") is determined regularly by local assessors and does not affect market price.
Zoning
R-1 / R-2
Rural Conservation Single-Family Residential District
The Rural Conservation Single-Family Residential District is intended to conserve significant open space, both upland and lowland, consistent with the preservation goals and policies contained in the Comprehensive Plan, and in a manner that respects the equity of landowners and the ability of developers to subdivide land at a density not to exceed one dwelling unit per five acres as applied pursuant to Section 275-33 G. Density bonuses may be granted pursuant to Section 275-33 I. In conformance with the City's Comprehensive Plan and with state enabling legislation, the purposes of this section also include: To conserve open land, including those areas containing unique and sensitive natural features such as woodlands, steep slopes, streams, floodplains and wetlands, by setting them aside from development; To provide design flexibility and efficiency in the siting of services and infrastructure, including the opportunity to reduce length of roads, utility runs, site grading, and the amount of paving required for residential development; To reduce erosion and sedimentation by the retention of vegetation and the minimization of development on steep slopes; To promote the infiltration of stormwater on site, thereby helping to recharge groundwater supplies; To provide for a diversity of lot sizes and building densities to accommodate a variety of age and income groups and residential preferences, so that the community's population diversity may be enhanced; To implement adopted City policies to conserve a variety of irreplaceable and environmentally sensitive resource areas, including provisions for reasonable incentives to create a conservation system for the benefit of present and future residents; To minimize impacts on environmental resources sensitive areas such as wetlands, floodplain, and steep slopes and disturbance of natural or cultural features such as mature woodlands, hedgerows and tree lines, critical wildlife habitats, historic buildings, and fieldstone walls, as well as to provide opportunities to enhance or restore existing resources that have been diminished or degraded through past land management practices; To protect areas of the City with productive agricultural soils for continued or future agricultural use, horticultural use, or other conservation use; To create neighborhoods with direct visual access to open land, with amenities in the form of neighborhood open space, and with a strong neighborhood identity; To provide for the conservation and maintenance of open land within the City to achieve the above-mentioned goals and for active or passive recreational use by residents; and To conserve scenic views and elements of the City's rural character by limiting views of new development from existing roads.
Permitted uses
Include but are not limited to:
Housing-Single unit
Housing-Other
Fire house
Police station
Property details
Interior
Basement Information
Basement Sq. Ft: 2,400
Basement Finish: Finished
Basement Type: Finished
Bathroom Information
# of Full Baths: 2
# of 1/2 Baths: 1
Heating & Cooling
Heating Fuel Type: Gas
Fireplace Information
Has Fireplace
Room Information
# of Rooms: 8
Exterior
Exterior Information
Building Style Type: Ranch
Property Information
Living Sq. Ft: 3,217
Ground Floor Sq. Ft: 2,400
Building Sq. Ft: 4,800
Legal Description: LOT 1 OF CSM 10837 BEING A COMBINATION OF LOTS 1 & 2 OF CSM 10763. BEING PT OF THE NE .25 OF THE NW .25 OF SEC 21 T6N R20E DOC #3804033 REC 12/29/2010
Lot Information
# of Buildings: 1
Land Sq. Ft: 436,471
Legal Lot Number: 1
Municipality Name: NEW BERLIN CITY
Acres: 10.02
Zoning Code: R1
State Use Description: RESIDENTIAL
Utility Information
Sewer Type: Septic
Water Service Type: Well
Utility Type: Gas Public
Financial
Assessor Information
Assessment Year: 2025
Tax District County: NEW BERLIN CITY
Public facts
Beds: 3
Baths: 2.5
Sq. Ft.: 3,217
Stories: —
Lot Size: 10.02 acres
Style: Single Family Residential
Year Built: 2011
Year Renovated: —
County: Waukesha County
APN: NBC 1234999009
Home facts updated by county records on Jun 15, 2026
Around this home
Schools
Ronald Reagan Elementary School
Public PreK-6 • Assigned • 0.6mi
6/10
New Berlin Middle/High School
Public 7-12 • Assigned • 1.3mi
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
1/10 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
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34
18
50
30
59
39
66
46
79
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82
64
78
61
76
56
65
46
47
34
33
20
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
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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
$1.07M – $1.29M
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