Boston Investment Property Guide: Buying and Selling Multifamily and Mixed-Use

Who this guide is for

• Investors buying their first or next 2–12 unit building in Boston or nearby cities.
• Owners selling a 3-family, multifamily or mixed-use building who want an agent who understands rent rolls and investor buyers.
• Small developers weighing a condo conversion or new construction.

Boston and South Boston neighborhoods for investors

Qualitative overview only; no prices, rents or cap rates are quoted. Ask us for current comps.

• South Boston: strong demand for both rentals and condos; a common market for triple-decker conversions and small new-construction townhouse projects. KM represented the buyer of the 421 East Sixth Street development site and is now selling the new residences there, and it also represented the buyer of a 3-unit building on W 8th Street (see the Telegraph Hill guide).
• Mission Hill: transit-oriented corridors with apartment and mixed-use buildings near hospitals and universities. KM represented the seller of 820–824 Huntington Avenue, a six-unit mixed-use building (four residential, two commercial units), which sold for $2.8M in August 2026.
• Greater Boston / Boston neighborhoods: a mix of 2- and 3-family housing stock, corridor mixed-use, and Downtown Boston luxury condos.
• East Boston: waterfront and transit-served neighborhood with a large stock of 2- and 3-family homes and ongoing new development; popular with rental investors and small-scale developers.
• Jamaica Plain: established residential neighborhood with multifamily housing, triple-deckers and condo buildings near green space and transit; demand comes from both owner-occupants and renters.
• Somerville, Quincy, Brookline and Norwood: nearby cities and towns with their own multifamily and condo markets and their own zoning and permitting rules. KM has closed 2-family investment sales in Quincy and Norwood. See Somerville, Quincy, and Brookline.

Recent KM investment sales

Through a direct-mail campaign, Kirsten connected with the owners of an off-market lodging house at 46 Winter Street in Quincy, who wanted their residents to keep their homes. She brokered the sale to Caritas Communities, preserving 17 units of deeply affordable housing. She then helped Caritas secure the adjacent lot at 50 Winter Street, and Caritas is combining the sites for Midwinter Apartments, a planned 34-unit affordable building.

KM has also closed several off-market investment sales, including 360 Athens Street in South Boston. See the projects page.

Multifamily, mixed-use and condo conversion basics

• Multifamily (2–4 units): often bought by owner-occupants or first-time investors; many lenders treat 1–4 units as residential lending.
• 5–12 units and mixed-use: generally treated as commercial real estate, with commercial financing, and value tied more to income and leases. Mixed-use adds retail or office leases to review.
• Condo conversion: turning a multifamily into individually sold units. Typical work includes a feasibility review, a survey and plans, a master deed and condo documents prepared by an attorney, any permits or building upgrades, and a marketing plan for the units. Tenant rules can apply in Boston; get legal advice before planning a conversion. (Full guide coming.)
• Commercial real estate development: for ground-up or substantial rehab projects, KM advises on pre-construction pricing and unit mix and handles sales (developer representation).

KM also represents investors buying luxury condos that need renovation.

Steps to buy an investment property in Boston

1. Set the strategy: hold for income, value-add, or conversion/sell-out. This decides which buildings fit.
2. Line up financing: talk to a lender early; residential and commercial loans differ for 1–4 vs 5+ units.
3. Pick neighborhoods and building types that fit the strategy.
4. Review the numbers the seller provides: rent roll, leases, operating expenses, utility setup and tax bill. Verify them; don't rely on pro formas.
5. Inspect: building, systems, and any code or permit history. Check zoning for what you plan to do.
6. Offer and negotiate, with contingencies your attorney recommends.
7. Diligence and close with a real estate attorney; review leases, deposits and estoppels as applicable.
8. Plan operations: leasing, management and maintenance from day one, or the conversion and sales plan.

(Not legal, tax or financial advice. Consult your attorney, CPA and lender.)

How KM Real Estate Group helps investors

• Buyer representation: sourcing on- and off-market multifamily and mixed-use, underwriting review, negotiation.
• Seller representation: pricing, marketing to investor buyers, diligence and negotiation through closing (e.g., 820–824 Huntington Ave).
• Buyer track record: 421 East Sixth St, 163 W 8th St, 41–43 Miller Stile Rd and 204 Walpole St (see Recent KM investment sales).
• Developer representation: pre-construction pricing, marketing and sales for new construction and conversions (e.g., 421 East Sixth Street).
• Permitting coordination.
• Property management: leasing and management after you buy, so sales and management are in one firm.

Talk to KM about your building. Call (781) 307-8843 or email kirsten@km-regroup.com.