Hidden cost drivers

Two offers with the same bottom line can include wildly different amounts. These four items are the most common places where costs "disappear" or get moved out as an option.

1. The meter cabinet — the biggest hidden difference

One vendor installs a complete new meter cabinet; another only does a §14a modernisation of the existing one. With old cabinets (e.g. from 1972) the difference can be €1,350–4,200. Ask explicitly: does the modernisation suffice, or is a new cabinet needed — and is it in the price?

2. Metal tiles / roof integration

Tiles adapted for mounting or replaced with metal/solar substitute tiles are often listed as an option. In one real case: about €1,425, not in the base price. If you want them, have them firmly included — otherwise you're comparing apples with pears.

3. Backup / Ersatzstrom

As in the backup chapter: almost always a separate line item (box + wiring). An offer without a backup item is cheaper — but you get nothing in an outage.

4. Wallbox: device vs connection only

"Wallbox prepared" often just means the connection is there, not the device. Difference roughly ~€1,200. Clarify whether the charger itself is included.

The golden rule

Normalise every offer to the same scope before comparing prices. Treat options consistently (in every total or none), always include the battery (often in its own chapter), and compare the meter-cabinet scope explicitly.

And: for figures read via OCR/photo, verify visually against the source PDF — digits get misread.

In short: the four usual hiding places are the meter cabinet, roof tiles, backup, and the wallbox device. Bring every offer to identical scope, then compare prices — otherwise the apparent winner is whoever left the most out.

That completes the "from concept to system" stage. Now comes the part many people are really here for: control & independence.