We have sat across the table from customers holding competitors' proposals for thirteen years. These are the twelve questions that reliably separate companies that will still be servicing your system in 2040 from companies that will not. Ask us all of them too.
1. What is the cost per watt, installed?
Total price divided by system size in watts. It is the only figure that lets you compare bids for different system sizes. Any company that will not state it is relying on you not being able to compare.
2. What is the cash price and what is the financed price?
These are different numbers, and the gap is the dealer fee that subsidises low-rate solar loans, often 10–30% of the financed amount. A 2.99% loan is not free money. Ask for both prices on the same design.
3. What module and inverter, by model number?
Not “Tier 1 panels.” Not “premium equipment.” A manufacturer and a model number, in the contract. Substitution after signing is one of the most common complaints in this industry.
4. Does your workmanship warranty cover roof penetrations, and for how long?
This is the question we most wish customers asked. Many workmanship warranties exclude roof leaks entirely, or cover them for ten years while the array is warranted for twenty-five. Get the answer in writing.
5. Who physically installs the system?
Employees or subcontractors? If subcontractors, which company, and who carries the warranty if that subcontractor stops working with them? There is nothing inherently wrong with subcontracting, but you should know the answer before you sign, not after a leak.
6. What is your production estimate based on?
Ask to see the shade analysis. A credible estimate comes from software modelling your actual roof geometry hour by hour across a year. An estimate derived from a regional average and a satellite screenshot is a guess with a decimal point.
7. Is there a production guarantee, and what does it actually pay?
Many companies offer a guarantee that pays out at a rate so low it is decorative. Ask: what percentage triggers it, at what rate is the shortfall reimbursed, and how many times have you paid one?
8. What rate escalation are you assuming in the savings projection?
Savings over 25 years are extremely sensitive to this number. At 2% annual utility escalation the projection looks modest; at 6% it looks spectacular. If it is not stated on the proposal, the number is doing work it should not be.
9. Which federal or state incentives are you including, and under what authority?
Especially in 2026, with the residential federal credit expired for newly placed-in-service systems. Ask which code section. Ask them to show the projection with the incentive removed.
10. What happens if the city inspection fails?
The right answer is “we fix it and re-inspect at our cost.” It is worth hearing them say it.
11. What is your average time from contract to permission to operate, in my city?
A company that knows this number tracks it. A company that answers “four to six weeks” for every jurisdiction in the state does not.
12. Can I speak to three customers in my area whose systems are over five years old?
Not new customers. Anyone can produce a happy customer from last month. Five-year customers have been through a service call, a warranty question, or a roof issue. Their experience is the one that predicts yours.
If a company answers all twelve without hedging, they are probably worth hiring, and it might not be us. If they get defensive at question four, you have saved yourself twenty-five years of regret.