Three places installation quotes quietly get padded

Three lines account for most of the padding: a lumped compliance and registration fee with no breakdown, battery capacity quoted as a headline number larger than its usable kWh, and one sundries line covering mounting, cabling and protection that nobody itemises.

1. Compliance as a mystery lump

A Certificate of Compliance, SSEG registration and engineering sign-off where required are real costs. They are also specific costs. A quote showing one round R15,000 compliance line deserves one question: break it down. Put two breakdowns side by side and the padding usually shows itself.

2. Battery capacity, headline vs usable

A battery sold as 5 kWh may offer about 4.5 kWh usable at a 90% depth of discharge, and less if the installer sets a higher reserve. That is physics and settings. It becomes padding when you pay for 10 kWh and receive far less usable. Ask for usable kWh in writing.

3. Sundries that swallow the roof

• Mounting structure for your actual roof type: tile, sheet or flat.
• DC and AC cable runs, measured, not guessed.
• Surge protection and a separate solar distribution board.
• Trunking, isolators and labelling.

Each item is legitimate. Together, as one unexplained line, they can hide R5,000 to R20,000 of margin on a mid-size job. Two itemised quotes at the same system size are the cheapest protection available. They cost an afternoon.