Sunrun Lease Buyout: Run the TCO Math Before You Call

The short answer

If you have six or more years left on a Sunrun solar lease and you plan to stay in the house, buying out usually beats continuing the payments. If you have under four years left, running the lease out is almost always cheaper.

That's the punchline. What follows is how I got there—because the buyout quote Sunrun sends you is one number inside a list of about nine.

Small correction before I go further: if you ended up here searching "lunar battery sunrun," the only battery Sunrun markets directly is the Brightbox. "Lunar" is a name that floats around in forum threads and I couldn't find it in any official Sunrun material—the product it points to is the Brightbox. Worth knowing before you build a quote around a product name that doesn't exist.

Why this number holds up

I've run procurement for a 180-person company for six years—about $370,000 a year of facilities budget. My job is to take quotes apart on a spreadsheet no matter how clean they look. I priced a solar PPA for a 140,000 sq ft campus and, because I apparently can't turn it off, applied the same file to my own Sunrun lease at home.

When I bought out our system in 2023, I had 41 months of utility bills, every lease payment, and the production records in one sheet. Not because I'm a natural spreadsheet person (I am, but that's not the point). Because I'd already been burned once on a "no-cost" contract that ended up costing $1,900 in admin fees I never priced in.

What the buyout quote is actually replacing

Here's where most people get the arithmetic wrong. They treat the buyout price as an add-on to the lease. It isn't. It replaces your remaining lease payments. Compare the buyout quote to (remaining months × monthly payment) and you see the real spread.

Seven years left at $118 a month is roughly $9,900 in payments you still owe. A $6,200 buyout quote isn't "another $6,200"—it's a net saving of about $3,700 against the rent, plus you end up owning the system.

I nearly got this wrong myself. My first pass treated the buyout as a new line item and the math said don't bother. Then I sat down and asked what the buyout was replacing. Different answer entirely. If you only take one thing from this post: the buyout price competes against your remaining lease payments, not against the system's sticker price.

The three line items that quietly kill the math

1. Inverter replacement

Inverters typically get swapped somewhere between year 12 and year 15. Under the lease, that's Sunrun's problem. Own the system and it's yours. When I ran the budget in early 2024 for that future replacement, I used three local installers' quotes—$2,200 to $3,500. Not a web estimate. If your system is already past year 11, add that number to the buyout cost before you decide anything.

2. Roof work

If the roof under those panels needs replacing in the next eight years, you're paying for detach and reinstall out of pocket once you own the system. Under the lease, that headache has a different owner. I've watched people skip the buyout for exactly this reason—their roof had three years left. Reasonable call.

3. Transfer at sale

This one gets no attention. While leased, a buyer has to agree to take on the lease—and if they won't, that's a conversation you don't want. Post-buyout, the panels are just part of the house. Usually that helps. In a soft market, though, a clean assumable lease can be easier to sell than an owned system with a roof question attached. It depends on the market, and anyone who tells you otherwise is guessing.

Battery and EV charger—two separate purchases people merge

If you're thinking about adding a Brightbox during the buyout conversation, price it separately. The battery sits on its own quote and its own warranty terms. Same with home charging: Sunrun is not an EV charger installer in most markets. In Ford Heights, a 240V circuit plus a wall charger is basically a licensed electrician job, and the honest range in 2025 money is $900 to $1,500 depending on panel distance. Whether your car is a CLA-Class EV or anything else barely moves that number—the circuit does, not the badge on the hood.

Electricians will also quote you a "standard install" that assumes an empty bay and a panel with capacity. Neither is guaranteed. Ask what the quote excludes. (I didn't, once. $380 in drywall and permits later.)

When not to buy out

Three situations where the lease is the better deal:

• Under four years left. The buyout quote is sized for the remaining contract, then priced for ownership. Past a certain point, you're paying a premium for a few years of ownership you won't recover.
• Year 11 or later, and you're staying put. Once you add inverter replacement and roof risk, a fair number of people find the lease is cheaper on a total-cost basis—even though it feels wrong.
• Selling within three years in a slow market. Let Sunrun carry the lease transfer risk. The savings from owning won't kick in before you move.

The buyout process itself is less dramatic than the math. You call, they send a quote with an expiration date, and if the date passes, you ask for another. Nothing about that changes because you waited two weeks.

One last thing I should add: the quote I got didn't itemize how it was calculated. I asked for the components anyway. I never got a full formula. The number was the number. Which is exactly why the rest of the TCO sheet matters more than the quote itself—you can't audit what they won't show you, so control the parts you can.