Partition wall between semi-detached houses - Who pays for what?

Hello,

I am a total beginner and have no idea about many technical and legal matters.
Nevertheless, we decided to build a semi-detached house with a developer. The other half has already been built by others and no partition wall and protective casing have been installed yet.

And now the question is: who pays for the house partition wall and protective casing between the two semi-detached houses? Do both semi-detached house owners have to share the entire cost?

I received an additional charge from my developer for the delivery of the house partition wall panel and the corresponding installation, for the neighbor's part because the developer only has one contract partner with me,

allegedly he is not allowed to conduct negotiations with the neighbor. He said that I have to clarify that myself with the neighbor.

It would be very helpful for me if you could share your suggestions or experiences.

Thank you very much in advance for your time and excuse me for my language mistakes.

Best regards
Prakash.

Hello Prakash,

The other half has already been built by others and no partition wall and formwork protector have been installed yet.

That can hardly be true. If one half already exists, there is also a party wall (neighbor's wall just before their border).

What exactly does your developer demand you to pay?

Rhenish greetings