Most home buyers treat solar panels like a bonus appliance. They see the seller’s pitch, assume the system works, and move on. Then they close on the house, get their first electric bill, and start asking questions nobody thought to ask six weeks earlier.
Here’s the truth: a standard home inspection does not cover solar panels. The inspector will check the roof for leaks, but they are not evaluating whether the solar system is functional, correctly installed, or worth anything. That gap is your problem to solve before you hand over a check.
I’ve been doing solar in Southwest Florida for a long time. I’ve seen buyers inherit systems that don’t work, systems that were oversold to the previous owner, and systems with serious code violations the seller didn’t know about or didn’t bother to disclose. If the house you’re buying has panels on the roof, here’s what to look at before you close.
Start with the Most Basic Question: Is It Working?
You’d be surprised how often the answer is no.
Solar systems can stop working for a lot of reasons. An inverter fails. A breaker trips and never gets reset. A monitoring account expires, and nobody notices that the system dropped offline two years ago. From the street, everything looks fine. Panels are still on the roof. The seller has no idea.
If the system has a monitoring platform, get access to the historical production data before closing. Look for gaps, drops, or anything that looks off. If you can’t get monitoring access, hire a licensed solar contractor to inspect the system before you close. They can pull up inverter data, test the system, and tell you whether it’s actually producing power.
This is the first thing to verify. A non-functional solar system on the roof is not an asset. It’s a liability with a pretty face.
Don’t Trust the Seller’s Production Claims
Sellers almost always overstate solar performance. Not always intentionally, but the result is the same for you.
I hear it constantly: “The seller said they get a zero electric bill.” Then the buyer moves in, turns the air conditioning to 72, heats the pool, and gets a $180 bill. What happened?
A few things could be going on. The previous owner may have had completely different usage habits. The system may have degraded over time. The seller may have been comparing a low-usage shoulder season to what the buyer will need on a hot August afternoon. Or the seller may have been repeating what the original installer told them at the time of the sale, which was probably itself a best-case scenario.
The only numbers that matter are verified historical production, ideally two to three years of actual data. Compare that against what the home actually consumed during the same period. Then think hard about how your usage will differ from the previous owner’s. If you work from home and run more loads, or you keep the house cooler, or you have more people living there, the math changes in a hurry.
Get that analysis done before you decide what the solar system is worth to you.
Know What the System Can and Cannot Do
Grid-tied solar without battery backup goes down when the utility goes down. That is not a malfunction. That is how it is supposed to work.
A lot of buyers are genuinely shocked to learn their solar system provides zero backup capability. When FPL shuts off power during a hurricane, the system shuts off automatically for safety reasons. The panels are on the roof, the sun is shining, and you’re sitting in the dark with everyone else on the block.
If backup power matters to you, find out whether the system has a battery component before you close. If it doesn’t, factor in the cost of adding one. Battery systems from manufacturers like Tesla, EG4, or FranklinWH can often be integrated with existing solar installations, but compatibility depends on what’s already installed. Some older inverter platforms don’t support battery retrofits cleanly, which means a more involved upgrade.
Don’t assume. Ask specifically whether the system has battery backup. If so, find out what loads it covers and for how long under real-world conditions.
Evaluate the Equipment Quality
Solar panels are designed to last 25 years. The inverter in that system might have a 10-year warranty. Some of the cheaper string inverters from a decade ago carried warranties as short as five years. When the inverter fails after the warranty window closes, that repair or replacement cost lands on you.
Inverter quality matters. Microinverter systems from Enphase have a different risk and cost profile than string inverter systems. Some string inverter brands have strong track records. Others have a long history of failures, service calls, and discontinued product lines. A licensed solar contractor can tell you in about five minutes what you’re working with.
Panel manufacturer health is another concern. Several solar panel companies have gone bankrupt over the past decade, and their warranties effectively died with them. SunPower is the most recent high-profile example. Their monitoring platform is essentially useless now. Their warranty program has become difficult to enforce. Homeowners with SunPower systems are navigating real, ongoing problems with parts, support, and monitoring options. That is not a hypothetical future risk. It is happening right now in Southwest Florida.
Check the brands. Find out if the manufacturer is still in business, whether the warranty is still supported by a real company, and what the expected remaining life looks like on the major components.
Look Hard at the Workmanship
Poor installation work is more common than it should be. We see it consistently.
The most frequent problem is wire management. Wires hanging loose from the panels, resting against the roof surface, rubbing against metal flashing or other edges. Over time, those wires degrade. Insulation breaks down. That becomes a safety issue and a code violation. Loose conduit is another common one, both on the roof and on exterior walls.
A standard home inspection will check the roof for leaks, but the inspector is not evaluating the solar installation specifically. They’re not looking at how the conduit was run or whether the wire management meets code. A solar contractor doing a dedicated pre-purchase inspection will look at all of this and document what they find.
If the workmanship is sloppy, you have two options: budget for corrections, or use the findings to negotiate with the seller. Either way, you want to know before you close, not after.
Understand the Maintenance Picture
Solar systems are mostly low-maintenance, but “mostly” is doing a lot of work in that sentence.
Inverters have expected lifespans. Monitoring systems can go obsolete or lose manufacturer support. Battery systems have cycle life curves and capacity degradation over time. If any component of the system is approaching end of warranty or end of useful life, you need to know that now so you can price it into the deal.
Ask the seller for all service records and maintenance history since the system was installed. Find out if there have been any inverter replacements, panel swaps, or repair calls. If the system is 10 or 12 years old and still running the original string inverter, a replacement is not a distant hypothetical. It may be one hot summer away.
In Southwest Florida, panels themselves stay reasonably clean. The afternoon rain does most of the work. But that doesn’t mean the rest of the system takes care of itself indefinitely.
Calculate What the System Is Actually Worth
Solar systems have real value. They also get wildly inflated in sellers’ minds. Here’s how to think about it clearly.
The first approach is future savings. Take verified annual production, run it against current FPL rates and the expected escalation in electricity costs, and project those savings over the remaining useful life of the system. Discount that figure back to present value and you have a reasonable starting point.
The second approach is replacement cost. What would it cost to install a comparable new system on that house today, with current equipment and current labor? How does the age and remaining life of the existing system compare? A 10-year-old system with 15 more viable years isn’t worth what a brand-new system would cost, but it’s also not worth zero. The math lands somewhere in the middle, and a solar contractor can help you figure out where.
That consultation will probably cost you a couple hundred dollars for the inspection and analysis. Compare that to the cost of buying a system that underperforms your expectations by $100 a month for the next decade.
The Bottom Line
Buying a house with solar panels in Southwest Florida can absolutely be a smart financial move, but only if you go in knowing what you’re actually buying. Get a pre-purchase inspection from a licensed solar contractor before you close. Verify production data. Understand the equipment brands, age, and warranty status. Find out whether the system has backup capability. And do the math on what the system is genuinely worth to you, not what the seller says it’s worth.
