Four checks at the property decide what becomes an extra line item later: the meter standing at the boundary, the distribution board and where the supply enters the house, the usable north-facing roof area left once chimneys, geysers, skylights and parapets are subtracted from the total roof, and where the shade falls at the hours that actually cut production rather than the hour a site visit happens to land on. None of these require a quote to be requested first, and a quote written before they are done is a guess with a price attached to it.
I want you standing where I stood. Corner of the yard, quarter past four on a June afternoon, sun already low in the north-west, and the front third of my roof sitting in shadow thrown by the neighbour's double-storey. I had a quote in my hand at that point. Eleven panels, north-facing, nothing on the page about a wall that would eat the last hour and a half of every winter afternoon.
So this is not about equipment. It is about the house.
Start in the yard at the hour that hurts
Nobody does a site visit at four in the afternoon in June. They do it at eleven in the morning, in a month that suits them, sun high, everything looking generous. The number that comes back is then optimistic by exactly the amount the winter afternoon takes away.
So walk it yourself, at the two times that matter: nine in the morning and four in the afternoon, in June or July. Stand where you think the panels will go and look along the roofline. Take a photo each time, with the time written on it. Then work out what you are actually looking at. The neighbour's double-storey. A palm. A blue gum three doors down. A solar geyser on the outbuilding. A parapet that throws a hard line across the first row of whatever eventually goes up there.
Three things I have learned to write down in that note.
The first is that trees grow. The hedge that is fine now is a green wall in four years, and the shading problem arrives long after the panels are paid for.
The second is that the shadow that matters is the one on the panel, not the one on the lawn. A whole roofline in shade at four is not automatically a problem. A small hard shadow across the bottom third of a north-facing plane is.
The third is that this finding changes the layout, the row spacing, and sometimes the whole approach to the design, and all of that lands in the price. It is far cheaper to find it in June with your phone than in July with a truck in the driveway.
If you want to be tidy about it, a horizon-profile app will give you the sun path for that exact spot. I use one and then confirm by walking the yard on a clear June morning, because the app does not know about the neighbour's approved second storey.
The roof, minus everything that is not roof
The number that ends up on the quote is not the size of your roof. It is the usable area on the north side of it, and the gap between those two numbers is where quotes get rewritten.
Walk the perimeter and write down what the covering actually is. IBR or Chromadek sheet, corrugated sheet, concrete tile, clay tile, slate, thatch, and in older suburbs, asbestos cement. Then the condition: rust blooming around the fixings, sheets that flex when you press them, sagging lines along the battens, water staining on the underside visible from the ceiling trapdoor. Sheet thickness matters on steel roofs, and so does what the sheets are fixed to. Purlins and trusses carry the panels plus wind load, and the question is not whether a bracket will hold, it is whether the structure was ever designed with a few hundred kilograms of extra dead load and a lot more uplift in mind.
That is not a judgement I make, and it is not one a solar salesperson should be making either. If the timber is old, the covering is brittle, or the roof is asbestos cement, the assessment belongs to someone qualified to give it in writing. Asbestos cement is the one that catches people out, because it cannot be walked on and its removal is regulated work. That becomes a line item long before anybody discusses panel wattage.
Now subtract everything that is not roof. The chimney. The solar geyser and its tank. Skylights. Whirlybirds and vents. Dormers. A parapet, which needs a setback so it does not shade the first row. Then look at the shape. A house with a wide east and west pitch and one small north pitch is a completely different conversation to a roof that runs true north for its full length. That difference is measured in panels, and panels are measured in rands.
One thing that trips up almost everybody: a phone compass is not pointing at true north. Magnetic declination over South Africa is large, roughly in the high teens west in the northern provinces and closer to the mid twenties west in the Cape, and it shifts slowly. Check the current value for your area before you trust a bearing off a phone. The easy confirmation is solar noon, when the sun is due north and shadows point due south. If your roof plane is square to that shadow line, you have a true north plane. If it is not, you have a north-east or north-west plane, which still works but performs differently and should never be quoted as if it were north.
Wind is the other quiet one. A roof in a coastal suburb is loaded differently to the same roof on the Highveld, and the structural sign-off reflects that. Nobody puts it on a quote, but it is why some houses need reinforcement before a single rail goes up.
The board you photograph and never open
I do not open distribution boards. I photograph them. One shot square-on with the cover still on, one of the whole corner so the electrician can see the wall, the conduit and how the supply gets in. Two photos and a note about how old I think it is.
What the electrician is looking for when those photos land: whether there is a spare way for a dedicated circuit, whether there is physical room for an isolator and surge protection, how the earth leakage is arranged, and whether the board is old enough that the practical answer is replacement. A single earth leakage unit covering the entire house is a common arrangement in older South African homes, and it is also the arrangement most likely to nuisance trip once anything new is added. That is not a fault. It is a design that was never asked to do this job.
While you are outside, look at where the supply comes in. A lot of houses have the main switch and sometimes the earth leakage sitting in a kiosk on the pavement, with the board in the house acting as a sub-board. That changes the scope, the cable route and the price. Look for a visible earth electrode near the boundary box, and do not touch it.
The point of all this is simple. Board replacement sits outside the equipment quote. It is a separate supplier, separate labour, and it usually surfaces two weeks after you have signed something.
Which meter is standing at the boundary
Walk out to the meter and identify it properly. The old electromechanical credit meter with the spinning disc. A digital credit meter. A prepaid keypad meter. A newer smart meter. They behave very differently under reverse flow, and your metro's rules decide what happens next, including whether a meter change is eventually required as part of the SSEG process.
Two practical things come out of this, and both are money.
The first is position. If you intend to limit export at the point of supply, the sensing has to happen where the supply enters, which is usually at the boundary box and not where the inverter will live. If that box is on the far corner of the erf and the garage is on the opposite side, somebody has to pull a cable between them. That is a trench or a conduit run, and it is almost never in the first quote.
The second is behaviour. Depending on the meter model and the metro, reverse flow can be recorded as an event, and an event can trigger a site visit. Whether that costs you anything depends entirely on the municipality, so confirm it with them rather than with whoever is selling you the system.
Also note if the box is rusted shut, inaccessible, or full of the previous owner's wiring. That is a delay before it is a cost.
The order the paperwork runs in
This is the check that saves the most money and gets done the least, because it involves a phone call rather than a photo.
Metros run this differently. Cape Town has a formal SSEG application process that runs before installation, with a tariff structure attached. Johannesburg's process has historically required zero export. Tshwane, Ekurhuleni, eThekwini and most smaller municipalities each have their own version, and a fair number of smaller municipalities have no published SSEG process at all. That last case is not a green light. It is a gap, and you should know you are standing in it before you order anything.
Two things are constant no matter where you are. NRS 097-2-1 governs how the system is allowed to connect to the grid, and SANS 10142-1 governs the wiring itself. Above a certain system size, most metros also want the single-line diagram signed off by a registered professional engineer or technologist, which is another appointment and another fee. And because the application form wants the equipment details, you generally cannot complete it properly before you have a shortlist, which is a good reason not to pay a deposit before you have read the process.
While you are on the phone to the municipality, do the two calls nobody thinks about. The estate or body corporate, if you live in one, because architectural rules can override everything. And your insurer, because a system that was not disclosed can complicate a claim in a way that has nothing to do with the system being safe.
What goes in the file
Before you request a single quote, you should have a dated folder with these in it: photos of the meter and the boundary box inside and out, photos of the board with the cover on, a photo of every roof plane, the same north face photographed at nine in the morning and four in the afternoon in winter, a copy of your latest municipal bill, and a note of your metro's SSEG page and what it says about the order of application and installation.
That folder does two things. It makes every quote comparable, because everyone is quoting the same house. And it turns the surprises into decisions you made on purpose.
Then ask for the quote.
