If the roof is not yours to use
Establish who owns and controls the roof before anything else. If you rent, it is not yours to alter, and a landlord has to be part of the conversation from the beginning rather than being asked at the end.
If you own a unit in a multi-family building, find out what the governing documents say about common elements and who has authority over the roof. That determines whether a personal installation is possible or whether a building-level project is the sensible route.
Ask your utility what options exist for customers who cannot install on their own roof. It is a short call and the answer is worth having before concluding that solar is unavailable to you.
One thing that does not depend on owning the roof: under 830 CMR 62.6.1 the Massachusetts solar and wind energy credit is available to an owner or tenant of a residential property who occupies it as their principal residence. Ask a tax advisor how that applies to your circumstances.
If you own the building
Massachusetts credits exported solar through net metering at or near the retail or basic service rate, and the SMART incentive is paid on metered production for a fixed term of 10 years for residential systems under 25 kW.
Confirm eligibility first. SMART is provided to customers of Eversource, National Grid and Unitil, and customers of municipal light plants are not eligible. Massachusetts has approximately 40 municipal light plants.
If the building is a rental you own, ask how net metering credit works when the tenant holds the electricity account, since that determines who receives the bill savings and who receives the incentive payments. Settle it before installation rather than after.
Confirm that a production meter is included and reporting, since the incentive is paid on metered production. A meter that quietly stops costs you part of a ten-year entitlement without any obvious signal.
Protecting yourself in a market with real money in it
Wherever a state offers genuine incentives there are people selling against them badly, and Massachusetts offers genuine incentives. That is a reason to be careful about who you sign with rather than a reason to stay out.
Get equipment specified by manufacturer and model number rather than by description, establish who honours each warranty and for how long, and ask what the workmanship warranty covers on roof penetrations specifically.
Ask any projection to show net metering credit and SMART payments separately rather than as one figure, and ask what it assumes after year ten when the SMART term ends. A model carrying the incentive through a twenty-five year projection is describing something that does not happen.
Do not sign at the kitchen table on the night of the first conversation. Take the paperwork away, read it, and get a second quote. An offer that is genuinely good will still be there next week.
Three state benefits, and the federal one that ended
Under 830 CMR 62.6.1 an owner or tenant of a residential property who occupies it as their principal residence is allowed a solar and wind energy credit against personal income tax equal to fifteen percent of the net expenditure for renewable energy source property, or $1,000, whichever is less, claimed on Schedule EC. It being available to a tenant as well as an owner is unusual and worth knowing.
Massachusetts also provides a property tax exemption of 100 percent for 20 years for solar installations, so the improvement does not raise your property tax bill the way a renovation of similar cost would.
And equipment for a solar system used as a primary or auxiliary energy source in a principal residence is exempt from sales and use tax. Check that your quote reflects that rather than assuming, and ask your municipal assessor what if anything they need for the property tax exemption at your address.
On the federal side, the 30 percent Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, so a cash or loan purchase now receives no federal credit. Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements, so ask any such provider what they claim and what of that value reaches you, and confirm with a tax advisor.