Duplex Property With Approved
New
For Sale
$1,199,000
401 W 4th St, Boston, MA 02127
MULTI_FAMILY - Boston, MA
Property Size2,795 SF
Lot Size0.03 Acres
Price / SF$428.98
Days on Market2
Property Features for 401 W 4th St
General Information
Property type
Residential Multi Family
Property subtype
Other
Property condition
Under Construction
Zoning
R1
Bedrooms
5
Bathrooms
5
Full bathrooms
5
Rooms
Bedroom 2, Bathroom 4, Bedroom 4, Bedroom 1, Bathroom 5, Bathroom 2, Bedroom 5, Bedroom 3, Bathroom 1, Bathroom 3
Directions
F st and W 4th st.
Subdivision
South Boston
Standard status
Active
APN
W:06 P:01094 S:000,1412683
Size
2,795 SF
Lot size
0.03 Acres
Taxes and HOA fees
Tax Year
2025
Tax Annual Amount
10222
Building Details
Year built
1900
Floors in Building
4
Number of units
2
Listing Agency:
Keller Williams Realty
(617) 969-9000
Listed By:
Keller Williams
(617) 969-9000
Added: Aug 13
Last Checked: Aug 14 at 10:06AM
MLS# 73563437
Copyright © 2026 MLS Property Information Network Inc. All rights reserved. All information provided by the listing agent/broker is deemed reliable but is not guaranteed and should be independently verified.
Investment Insights
Based on property information with market context.
This Boston property is a duplex asset with 2,795 square feet on a 0.0342-acre lot. The existing structure contains three floors of living space and a partially finished walk-out basement. Approved plans provide for two duplex units, with additional living area possible through the by-right FAR of 2.0. The property is zoned R1 and was built in 1900.
Tenants are currently in place through August 2026. The plans offer a defined path toward a two-unit layout while preserving flexibility for future ownership or occupancy strategies. The property is located at 401 W 4th St in Boston, Massachusetts.
Tenants are currently in place through August 2026. The plans offer a defined path toward a two-unit layout while preserving flexibility for future ownership or occupancy strategies. The property is located at 401 W 4th St in Boston, Massachusetts.
Key Highlights
- Approved plans for two duplex units
- 2,795 square feet on a 0.0342‑acre lot
- Three floors of existing living space
Financial Insights
Estimated NOI and Cap Rate
NOI = area × lease_rate × (100 − vacancy) / 100 × (1 − expense_ratio). Net Operating Income — what the owner takes home each year before mortgage payments and income tax. Effective rent (asking rent minus vacancy losses) minus operating costs (taxes, insurance, maintenance, management).
NOI / Yr
$70,628
Cap rate = NOI / list price × 100. Capitalization rate — annual return on a fully cash purchase, before financing. NOI divided by price. Higher means more income per dollar invested, but usually also more risk or older condition. 5–8% is typical for stabilized commercial property; double digits often signal distressed deals.
Cap Rate
5.89%
Suggested Prices Based on Cap Rates
Cap rates vary significantly by property type, market, and asset quality.
Typical U.S. stable-market ranges:
Multifamily — 4.5% to 6.5% (Class A in primary markets often sub-5%; Class C in secondary markets 6%+)
Industrial / Logistics — 5.0% to 7.0% (compressed heavily in recent years due to e-commerce demand)
Office — 6.5% to 9%+ (wide spread post-2020; CBD Class A vs. suburban Class B varies dramatically)
Retail — 5.5% to 8.5% (grocery-anchored on the low end, unanchored strip centers higher)
Hospitality / Hotels — 7.5% to 10%+ (higher due to operational risk)
Self-Storage — 5.5% to 7.5%
Medical Office — 6.0% to 7.5%
Net Lease (single tenant, credit) — 5.0% to 7.0% depending on tenant credit and lease term
Rules of thumb:
Primary markets (NYC, SF, LA, Boston, DC) trade at lower cap rates than secondary/tertiary markets, often by 100–200 bps (bps, aka basis points; 1 bp = 0.01%).
Class A assets trade ~50–150 bps tighter than Class B, and Class B tighter than Class C.
Cap rates move inversely with price — a lower cap rate means a higher price for the same NOI.
Spread to the 10-year Treasury is a common benchmark; historically 200–400 bps over the 10-year.
Cap Rate 5%
$1,412,560
$1.4M
Cap Rate 7%
$1,008,971
$1.0M
Cap Rate 9%
$784,756
$784.8K
Market Conditions
NOI Build-Up for 2,795 SF
Vacancy — income lost from leasable area expected to sit empty during the year, subtracted from gross rent.
EGI (Effective Gross Income) — gross rent minus vacancy losses, the realistic income before paying operating costs.
OpEx (Operating Expenses) — recurring costs to operate the property (property tax, insurance, utilities, maintenance, management); excludes financing and capital improvements.
NOI (Net Operating Income) — income a property generates after operating costs but before financing and taxes.
Gross rent
$105.7K $37.80/SF
− Vacancy
−$4.8K −$1.70/SF
EGI
$100.9K $36.10/SF
− OpEx
−$30.3K −$10.83/SF
NOI
$70.6K $25.27/SF
Area
Boston, MA
Vacancy
4.50%
Lease Rate
$37.80 /SF/Yr
Expense Ratio
30.00%
Simulate Cap Rate and NOI
Suggested Prices Based on Cap Rates
Cap rates vary significantly by property type, market, and asset quality.
Typical U.S. stable-market ranges:
Multifamily — 4.5% to 6.5% (Class A in primary markets often sub-5%; Class C in secondary markets 6%+)
Industrial / Logistics — 5.0% to 7.0% (compressed heavily in recent years due to e-commerce demand)
Office — 6.5% to 9%+ (wide spread post-2020; CBD Class A vs. suburban Class B varies dramatically)
Retail — 5.5% to 8.5% (grocery-anchored on the low end, unanchored strip centers higher)
Hospitality / Hotels — 7.5% to 10%+ (higher due to operational risk)
Self-Storage — 5.5% to 7.5%
Medical Office — 6.0% to 7.5%
Net Lease (single tenant, credit) — 5.0% to 7.0% depending on tenant credit and lease term
Rules of thumb:
Primary markets (NYC, SF, LA, Boston, DC) trade at lower cap rates than secondary/tertiary markets, often by 100–200 bps (bps, aka basis points; 1 bp = 0.01%).
Class A assets trade ~50–150 bps tighter than Class B, and Class B tighter than Class C.
Cap rates move inversely with price — a lower cap rate means a higher price for the same NOI.
Spread to the 10-year Treasury is a common benchmark; historically 200–400 bps over the 10-year.
Cap Rate 5%
$1,412,560
Cap Rate 7%
$1,008,971
Cap Rate 9%
$784,756
Alternative Uses
Best Use
Multifamily LT 5
$1.01M
$882.9K – $1.18M
NOI $70,628 @ 7.0% cap · market cap 5.89%
Second Best
Apartment 5plus
$938.0K
$820.8K – $1.09M
NOI $65,660 @ 7.0% cap · market cap 5.48%
Theoretical Best
Office A
$2.09M
$1.83M – $2.44M
NOI $146,503 @ 7.0% cap · market cap 12.22%
Zoning and permitted uses should be independently verified with authorities.
Property Analytics
Property Profile
Current Use
Location Intelligence
Trade Area within ½ mile
2,156
Businesses Nearby
Explore this area
Business Placement
Demographics for 02127, MA
37,939
Population
19,495
Households
1.9
Avg Household Size
31
Median Age
69%
College-Educated
95%
High-School Grad
2.1 sq mi
ZIP Area
18,066
Density / Sq Mi
$156,373
Median Household Income
$85,444
Median Earnings
$2,435
Median Rent
$858,600
Median Home Value
Market
Vacancy Rate% for Multifamily in Northeast region
Questions? Ask Rey
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Frequently Asked Questions
What type of property is this?
Duplex - Approved plans support a two-unit duplex configuration.
Where is this duplex located?
The property is located at 401 W 4th St Boston, MA.
What is the asking price?
The asking price for this property is $1,199,000.
What are key features of this property?
This property features: Approved plans for two duplex units; 2,795 square feet on a 0.0342‑acre lot; Three floors of existing living space
