Your List Is 80% of Your Campaign
Direct mail people love to argue about copy, design, and format. But the truth is, your list determines 80% of your results.
Send a perfect postcard to the wrong homeowner and you get nothing. Send a decent postcard to a homeowner with a $350/month electric bill and a 3-year-old roof? They'll call you.
Here's how to build solar mailing lists that deliver $67 leads instead of $1,929 Google Ads leads.
Data Source 1: Utility Rate Maps
The strongest predictor of solar readiness is how much the homeowner pays for electricity. Higher bills mean clearer financial motivation.
Where to find this data:
- EIA (Energy Information Administration) -- Free. Publishes average electricity rates by state and utility provider. Good for identifying high-cost markets.
- Utility company rate schedules -- Most utilities publish their residential rates online. Identify which providers charge $0.15+/kWh.
- Data providers (ATTOM, CoreLogic) -- Sell property-level data that can be cross-referenced with utility territory maps.
How to use it:
Map your service area by utility provider. Rank zip codes by average residential rate. Start with the highest-cost areas.
A homeowner paying $3,600/year for electricity in a $0.18/kWh territory has a fundamentally different reaction to "cut your bill by 70%" than someone paying $1,200/year in a $0.09/kWh territory.
Target the pain.
Data Source 2: Roof Age From Permit Records
A new roof eliminates the biggest objection to solar: "I don't want to deal with my roof."
Where to find this data:
- County building department -- Most counties maintain public records of roofing permits. Some publish searchable databases online. Others require an in-person records request.
- Zillow/Redfin -- Property listings sometimes mention "new roof" in the description. Not comprehensive, but free.
- Data aggregators -- Companies like BuildFax compile building permit data nationally and sell it in list format.
How to use it:
Pull all residential roofing permits issued in your service area within the last 24 months. Cross-reference with property ownership records to get homeowner names and mailing addresses.
These homeowners just spent $10,000-$20,000 on their roof. They're in "home investment" mode. Their roof anxiety is zero. Solar is the logical next investment.
Data Source 3: EV Registration Data
EV owners -- especially Tesla drivers -- are the highest-converting solar prospects in the market.
Why:
- Their electric bill just jumped $60-$100/month from home charging
- They already buy into clean energy technology
- They're comfortable with large purchases
- Tesla itself sells solar, so the concept is pre-normalized
Where to find this data:
- DMV data providers -- Companies like Polk (now IHS Markit), Experian Automotive, and R.L. Polk sell vehicle registration data by geography
- EV charger permit records -- County building departments that track Level 2 charger installations
- Cross-reference services -- Some data providers can match EV registrations to property records
How to use it:
Pull EV registrations in your service area. Match to property addresses (you want homeowners, not renters). Add to your list as a high-priority segment.
An EV owner in a high-utility-rate zip code with a newer roof is a near-certain solar buyer. That's a triple-stacked signal.
Data Source 4: Property Records (Assessor Data)
County assessor data is the backbone of any targeted mailing list. It tells you:
- Property value -- $300K+ for solar viability (financing qualification, homeowner equity)
- Year built -- Older homes may need electrical panel upgrades, but owners have equity
- Lot size -- Larger lots may have more roof area or ground-mount potential
- Owner-occupied vs. rental -- You want owner-occupied. Landlords rarely invest in solar for rentals.
- Owner name and mailing address -- Your mailing target
Where to find it:
- County assessor website -- Many counties offer free bulk data downloads
- Data providers -- ATTOM, CoreLogic, DataTree sell cleaned and formatted assessor data
- Title companies -- Often willing to pull lists for local businesses they work with
Data Source 5: HVAC and Permit Cross-References
Homeowners who recently installed new HVAC systems are thinking about energy efficiency. They just dropped $8,000-$15,000 on comfort. Solar extends the savings story.
Where to find it:
Pull HVAC permits from county building departments. Same process as roofing permits. Filter for permits issued in the last 12 months.
This is a smaller list but a high-intent one. These homeowners are in "energy upgrade" mode.
How to Stack Signals for Maximum Conversion
Single-signal lists work. Multi-signal lists work better.
Tier 1 (highest conversion): High electric bill + new roof in last 2 years + property $300K+ + owner-occupied
Tier 2: EV owner + high electric bill + property $300K+ + homeowner tenure 5+ years
Tier 3: Recent HVAC + property $400K+ + roof age 10-15 years + high utility rates
How many should you mail?
Start with your Tier 1 list. If it's 200 homeowners, mail all 200. If it's 2,000, start with 500 in the highest-rate zip codes.
At $1.35/card (Mailbots pricing for 200-999 pieces), a 500-piece campaign costs $675. At 1.89% average response rate, that's about 10 leads at $67 each.
List Hygiene: Don't Skip This
A dirty list wastes money. Before you mail:
NCOA (National Change of Address): Run your list through USPS NCOA processing to remove people who've moved. ~10% of Americans move every year.
CASS (Coding Accuracy Support System): Standardizes addresses to USPS format. Reduces undeliverable mail.
Remove existing solar: If you can identify homes with existing solar installations (satellite imagery, permit records), remove them. They're not prospects.
Remove renters: Cross-reference with ownership records. Only mail owner-occupied homes.
Deduplicate: If the same address appears in multiple data sources, send one piece, not three.
Most data providers and mail services handle NCOA and CASS automatically. Ask before you buy a list.
How Often to Refresh
Mailing lists decay. People move, homes sell, roofs get replaced, solar gets installed.
Recommended refresh cycle:
- Every 90 days: Re-run NCOA processing
- Every 6 months: Pull fresh property and permit data
- After every campaign: Remove addresses that generated returned mail
A list you bought 12 months ago is significantly degraded. Budget for regular data refreshes as part of your campaign cost.
The Bottom Line
The difference between a $67 solar lead and a $1,929 solar lead isn't the postcard -- it's the list.
Build a targeted list using utility rates, roof age, EV ownership, and property characteristics. Stack two or three signals. Clean the data. Then send handwritten postcards that reference their specific property.
Upload your solar list to mailbots.ai -- we'll write and mail handwritten postcards with per-piece tracking and QR attribution. From $1.10/card. No platform fees, no minimums.