Solar Guides
The Solar Bid Checklist: What Must Be in Writing
If it’s not in writing, it isn’t in the deal. Here’s the checklist we’d hand a friend before they sign anything.
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A handshake and a glossy brochure aren’t a contract. Everything below should appear, in writing, in the proposal or the contract itself.
System and production
- System size in kW (DC and AC)
- Estimated annual production in kWh, with the shading assumptions
- Panel make and model, count, and wattage
- Inverter type and model (microinverter vs. string — see our breakdown)
- Battery make, model and capacity, if included
Money
- Total cash price and, separately, the financed price and APR
- Any dealer or origination fees, stated as a dollar amount
- What incentives are assumed — and confirmation that no residential federal credit is included (it ended Dec 31, 2025)
Protection and process
- The full warranty stack: panel, inverter, workmanship, roof penetrations — and who services them. We use a 30-year Solar Insure warranty.
- Who pulls permits and handles interconnection
- A realistic timeline from contract to power-on
- The licensed contractor of record (license number)
If an installer balks at putting any of this in writing, that hesitation is the most useful data point you’ll get.
Good questions
Frequently asked.
What's the single most important written item?
The annual kWh production estimate — it’s the basis for every savings claim. No number, no accountability.
Should the contract name the equipment?
Yes. “Tier-1 panels” is not a model. Get the make, model, and wattage so a substitution can’t quietly happen later.
Go boldly
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