Buying a Valley home with solar already on the roof is usually good news. You get the production without the install cost. What you also get is a system with a history you know nothing about, maintained by someone whose habits you cannot verify, under panels you have never looked beneath.
Standard home inspections rarely cover solar in any depth. Most inspectors note that panels exist, confirm the inverter has power, and move on. The gaps below are yours to close.
Questions to Ask Before You Close
Get these in writing during your inspection period, not after.
Ownership Structure
This is the first question and it changes everything downstream. Owned outright, financed with a loan, leased, or on a power purchase agreement? A lease or PPA means the equipment belongs to someone else and transfers to you as an assumed contract with its own terms and its own credit qualification. Ask for the actual agreement, not a summary.
Age and Equipment
- Installation date and the installing company, and whether that company still exists
- Module manufacturer and model, plus the inverter type and model
- Whether the inverter has ever been replaced, since string inverters commonly need replacement before panels do
- Whether any modules have been replaced and why
Warranty Status
- Product and performance warranty terms on the modules
- Inverter warranty, which is typically shorter
- Workmanship and roof penetration warranty from the installer
- Crucially, whether each of these transfers to a new owner and what the transfer process requires. Some require notification within a window after closing. Missing that window can void coverage.
Production History
Ask the seller for monitoring app access or exports covering the last two or three years. This is the single most informative document you can get. A steady year over year decline tells you about soiling or a developing fault. A step change tells you when something broke.
What to Actually Look At
Some of this you can do from the ground with binoculars or a zoom lens. Some warrants a professional.
- Under the array. Look up at the gap between panels and roof from several angles. Nesting material, feathers, twigs, and droppings mean birds have been living there, possibly for years.
- Existing bird proofing. Is there mesh? Does it run the full perimeter or just the street facing edge? Is it clipped tight or sagging and torn? Partial or failed mesh is worse than none, because it can seal animals in.
- Droppings on walls and walkways below the roofline. Ground level evidence of a roof level problem.
- Panel surfaces. Look for cracked or shattered glass, cloudy or yellowed areas, visible delamination, and brown snail trail discoloration along cell edges.
- Mineral staining. White chalky edges or streaks mean someone washed these with a hose and tap water. Long standing hard water deposits can etch the glass permanently.
- Roof condition under and around the array. How old is the roof? If it needs replacement in the next few years, the panels have to come off and go back on, which is a real cost.
- Wiring. Conduit that is intact and secured, no sagging cable runs touching the roof, no exposed conductor. Chew marks near a rodent midden are worth a closer look.
- Inverter display. Any fault codes, error lights, or a blank screen.
Your First 30 Days as the New Owner
Once the house is yours, work through this quickly while you still have the seller's attention and the deal fresh.
- Transfer the monitoring account into your name and set up notifications. Do this first, because it takes a phone call and you will forget.
- File warranty transfer paperwork if there is a deadline attached.
- Book a full cleaning and inspection. Assume it has not been cleaned recently regardless of what you were told. This also establishes a clean baseline for your production data going forward.
- Clear and exclude. If there is nesting debris under the array, get it removed and get proper perimeter mesh installed. Sealing an occupied array is a mistake.
- Notify your insurance carrier that the property has solar and confirm how it is covered.
- Set your cleaning cadence based on your roof pitch, nearby trees, and dust exposure rather than a generic interval.
The cleaning and inspection visit is worth booking even if everything looks fine, because a technician on the roof will see the things you cannot see from the yard. It is a cheap way to convert unknowns into knowns.
Two Bits Solar Cleaning handles new owner visits regularly across the Phoenix area: a full deionized water wash, debris clearing beneath the array, an honest report on what we find up there, and bird proofing if birds have already moved in. Just closed on a place with panels? Let us take a look before you inherit someone else's deferred maintenance.