
12 Auburn Street Boston — Photo 1 of 36
$2,399,000
Investment Analysis — 12 Auburn Street
Boston, MA 02129 — Charlestown
Based on HUD Small Area Fair Market Rent for Boston-Cambridge-Quincy, MA-NH HUD Metro FMR Area, a 3-bedroom in 02129 carries an estimated $4,820/mo in gross rent — about a 1.20% cap rate and $28,800/yr in estimated NOI at the $2,399,000 list price. Adjust every assumption in the calculator below.
Beds
3
Baths
3.5
SqFt
3,360
Style
Single Family
Built
1880
Rich in historic character and offering an impressive approx. 3,360 square feet across four levels, this classic 1880 Charlestown brownstone delivers exceptional scale and versatility. The main and upper levels function as an expansive single-family home, with elegant living and dining rooms, an updated kitchen, soaring ceilings, intricate millwork, hardwood floors, oversized windows and four fireplaces. The expansive primary suite is a standout, complete with custom built ins, a fireplace and spacious en-suite bath with dual vanities, soaking tub and glass-enclosed shower. The top floor also offers the potential to be reconfigured into two bedrooms, adding an additional bedroom to the home. A private deck and patio extend the living space outdoors. Separate from the main residence, the garden level features a one-bedroom apartment with its own private entrance, offering excellent rental income potential or a guest suite. Located near the residence there is a deeded heated garage space available separately for purchase, and there are two additional parking spaces available to rent. Convenient to Main Street and all Charlestown has to offer, with easy access to Downtown Boston, the waterfront and major highways.
ADU Potential
Massachusetts allows one accessory dwelling unit by right in single-family zoning districts statewide (M.G.L. c. 40A §3; 760 CMR 71.00, effective Feb 2025). Estimated maximum ADU size for this property: 900 sq ft (the lesser of 900 sq ft or half the 3,360 sq ft principal dwelling). Lot size: 1,946 sq ft.
Based on listing data, which indicates the property type — not the zoning district. Local dimensional, septic (Title 5), and historic-district requirements still apply. Not legal advice — verify with the municipality.
Estimates — not financial advice
These figures are illustrative estimates for informational purposes only — not an appraisal, valuation, or guarantee of rent, income, or returns, and not financial, tax, or investment advice. Rent is either the figure reported on the MLS listing — in-place rent that may differ from market and is not verified against the actual leases — or, where the listing reports none, an estimate from HUD Small Area Fair Market Rents, a government benchmark that may differ from actual market rent. Each figure is labelled with its source. Cap rate, NOI, and returns depend on the assumptions shown, which you can change. MLS and other third-party data may be inaccurate or out of date. Verify all figures independently and consult your own financial, tax, and legal advisors before making any investment decision.
Property Details
Financials
Parking
Interior Specifications
Climate & Utilities
Building & Exterior
Property & Lot
Amenities & Appliances
Oven • Dishwasher • Microwave • Range • Refrigerator • Freezer • Washer • Dryer
Neighborhood
Public Transportation • Shopping • Park • Walk/Jog Trails • Medical Facility • Bike Path
Geography
Property History
$2,399,000
Sep 9, 2026
MLS® 73574730
$2,500
Jul 23, 2025
MLS® 73401425
$2,500
Jul 9, 2025
MLS® 73401425
Listing Agent: Tracy Shea
Listing Office: Coldwell Banker Realty - Boston
MLS® Number: 73574730


