Direct Answer
To hire a reliable hvac system replacement contractor in Cambridge: (1) Get 3 written quotes with line-item breakdowns, (2) Verify MA license at Massachusetts Office of Consumer Affairs (mass.gov/orr), (3) Confirm active general liability and workers' comp insurance, (4) Check Google and BBB reviews specific to Cambridge projects, (5) Never pay more than 10-30% upfront — never pay in full before completion.
Full Explanation
Red flags specific to Cambridge contractors: no physical Cambridge-area address, pressure to start immediately, cash-only payment demands, and license numbers that don't verify at Massachusetts Office of Consumer Affairs (mass.gov/orr). Seasonal demand during summer brings out less reputable contractors.
Local Factors in Cambridge
📍Verify license: Massachusetts Office of Consumer Affairs (mass.gov/orr)
📍File complaints: Massachusetts Office of Consumer Affairs (mass.gov/orr)
📍Homeowner protections under MA consumer protection law
📍BBB Greater Cambridge chapter for complaints history