The payment method is not a footnote - it decides who owns the system, who keeps the tax credit, and what your actual return looks like. We will walk through all four honestly, including the ones we do not sell.
Cash: The best return and the worst up-front number. You own the system on day one, you keep every incentive, and every dollar of avoided electric bill is yours. No financing cost eats into the payback.
Secured loan: Little or nothing down, and you still own the system and keep the tax credit and any rebates. Monthly payment plus a smaller electric bill usually lands close to your old bill, then the loan pays off and the savings become real.
Lease or power-purchase agreement: Little or nothing down, but a third party owns the panels, claims the tax credit, and sells you the power at a set rate. The contract is tied to the house and can complicate a sale. We will explain it, but for most people who can finance a purchase, ownership beats leasing - that is the plainest thing we can tell you.
If you can qualify for a secured loan, it usually beats a lease on total cost - you are paying for the same system either way, the loan just lets you keep what it produces.
What happens to your bill: This is the most misunderstood part. Net metering credits the power your system exports, but the rate and the rules vary by utility and have generally been getting less generous over time - so we model your current tariff, not the more favorable one your neighbor may have locked in years ago. Solar does not usually erase the bill entirely: most utilities keep a fixed connection charge regardless of how little grid power you draw.
Sizing from your real consumption: We size a system from twelve months of your actual electric usage, not from how much roof you have. Production is then estimated from your roof orientation, pitch, latitude, and any measured shading from trees or neighboring structures. A south-facing plane usually produces the most total energy over a year, but a west-facing plane often pays better under a time-of-use rate, because it produces more in the late afternoon when electricity costs the most.