Question: Why do I need a power of attorney from the seller? I thought the apartment would become my property, so I should have voting rights according to the co-ownership share at the owners' meetings.
You become the possessor from the date defined in the contract. Usually, this is the date when the full purchase price has been paid.
You only become the owner once you are registered as the owner in the land register by the court. This can sometimes take 6-9 months after payment.
The clause is to your advantage. Otherwise, the current owner could make resolutions at the owners' meeting after the transfer of possession, and you would have no voting rights.
But it's tough to receive the contract only shortly before the appointment. The notary can definitely expect a lot of questions during the notarization appointment.