Photovoltaic system at the multi-family house. 100% approval from the homeowners' association?

this is not a matter of opinion! Further information can be found under "WEG Reform 2020".

I told you. Since the reform, a simple majority. It’s not something I came up with.

Regarding the costs:

[*]The costs of the renovation are borne by the owners who agreed to the renovation measure. [*]If the renovation measure is decided with more than two-thirds of the votes cast and more than half of the co-ownership shares, according to § 21 para. 2 sentence 1 no. 1 WEG, all owners bear the costs – except if the structural change is disproportionately expensive. [*]According to § 21 para. 2 sentence 1 no. 2 WEG, all owners also bear the costs if the renovation measure amortizes within a reasonable period. An important reference point for this is the 10-year period applicable to modernizing repairs.

I told you so.

that's why the quote in the post :)

the thing about it being a matter of opinion referred to the "I see it differently" before.

The questioner is not concerned with renovation, but with the installation of a photovoltaic system! Here, he clearly asked whether all owners must agree when acquiring a photovoltaic system! It has nothing to do with renovation. Therefore, I cannot imagine that a simple majority - as with a renovation - is sufficient in this case!

That's why I can't imagine

It's not about "imagining" or believing. That's how it is stated in the law. Energy renovation. Period.

A photovoltaic system is not an energy renovation... Oh man. Oh man. He clearly writes "in addition to a renovation" a photovoltaic system is to be acquired... The renovation will probably be the facade. Photovoltaics are separate here! Renovation is clear. Simple majority of owners. But I see the point "acquisition of a photovoltaic system" differently. Here all owners must agree. A simple majority like for a facade renovation, for example, is not enough here.

Thank you very much for the answers. I now have the necessary information. So a simple majority is sufficient, but the system must also "pay off" within 10 years. If this is not the case, the system can be stopped by a veto from an owner. Not a simple topic. A large photovoltaic system would also significantly change the appearance of the house (major intervention). And not everyone is keen on having a photovoltaic system on their roof...