640 River Street Boston, MA 02126
Multifamily property in Mattapan with rent growth potential.
Property Features for 640 River Street
General Information
- Standard status
- Active
- Size
- 5,448 SF
- Property subtype
- Multi-family
Building Details
- Year Built
- 1920
Listing office Boston Realty Advisors
Listing date Nov 20, 2025
Source Stevebremis
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Investment Insights
Based on property information with market context.
Key Highlights
- Multifamily property featuring six 2‑bedroom/1‑bathroom units.
- Positioned for rent growth through in‑unit upgrades and releasing.
- Convenient access to downtown Boston via the Mattapan Line, bus routes, and Blue Hill Avenue.
Local Financial Insights For Apartment 5plus
Simulate Cap Rate and NOI
NOI Build-Up
- 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.
| Component | $ | $/SF |
|---|---|---|
| Gross rent | $241.9k | $44.40 |
| − Vacancy | −$9.2k | −$1.69 |
| EGI | $232.7k | $42.71 |
| − OpEx | −$104.7k | −$19.22 |
| NOI | $128.0k | $23.49 |
