Massive new construction with a basement - but how?

Hello, I want to start a new construction with a basement. The whole thing should be solidly built and such that it ideally achieves an energy efficiency house 55. Monolithic construction is preferred (preferably Poroton). Now I have many questions: 1. What wall thickness should I build? 2. If I have to insulate, which brick should I take and in what thickness and which insulation and in what thickness? The maintenance costs regarding heating should remain low. 3. What costs will I face? I would like price experiences of the construction variants you suggest. I am grateful for any help. Experience reports would also be helpful.

1. Depends on the material 2. It's a matter of belief, there is no all-rounder 3. Costs for what??? Shell construction? Walls? Complete construction? Too many details are missing!

Sorry...

... I think no one can give you an answer there. With normal equipment, expect 1200 - 1600€ per finished m² of living space. Poroton also offers perlite-filled bricks that at least meet your request for monolithic construction.

Otherwise, you could only consult the crystal ball :)